Difference between revisions of "Enemy AI"

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(Condition list fix)
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___________________________________________________________________
 
___________________________________________________________________
  
−
WaddlerD's conversation to me:
+
</pre>
−
___________________________________________________________________
+
  
−
WaddlerD 85: The AI tactics is quite interesting.
 
−
WaddlerD 85: All the monsters has 2 main patterns.
 
−
WaddlerD 85: A "normal", move on will pattern and a "counter, move
 
−
with the response of an attack or action, pattern.
 
−
WaddlerD 85: It's always seperated by FE FF
 
−
WaddlerD 85: The stuff between the FE FF is simple and complicated
 
−
in a way.
 
−
WaddlerD 85: The first 4 bytes are ALWAYS to going to be a
 
−
precondition.
 
−
WaddlerD 85: followed by a FE
 
−
WaddlerD 85: to seperate the precondition from the actual actions.
 
−
WaddlerD 85: I haven't found out all the preconditions yet, as there
 
−
are quite a few, but usually 00 00 00 00 is the default.
 
−
WaddlerD 85: As it means, "If the monster is alive" probaby.
 
−
WaddlerD 85: probably*
 
−
WaddlerD 85: You can put more than one precondition in a pattern,
 
−
though.
 
−
WaddlerD 85: Like for instance.
 
−
WaddlerD 85: FE FF 00 00 00 00 FE Blah blah blah FE 00 00 00 00 FE
 
−
Blah Blah FE FF <--- Normal attack pattern
 
−
WaddlerD 85: The four bytes.
 
−
WaddlerD 85: Though it's also good to know that the precondition can
 
−
be expanded into some big "and" precondition.
 
−
WaddlerD 85: Like for instance 01 03 00 00 15 40 00 00 = "When HP is
 
−
at 50% AND Monster is hit with Shadow based elemental attack.
 
−
WaddlerD 85: There is quite a few interesting preconditions that I
 
−
found out so far.
 
  
  
−
WaddlerD 85: Somewhat sloppy, but it should be good enough
 
−
WaddlerD 85: Byte #1: 00 = No Attack
 
−
01 = Attack
 
−
Byte #2: 00 = Normal Attack
 
−
01 = Secondary Attack
 
−
Byte #3: (Target?)
 
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Byte #4: Animation that is done before attack
 
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01 = Up Close
 
−
04 = Stand Still Action
 
−
0A = Circle around
 
−
0E = Going Astray
 
  
−
02 XX 05 XX XX XX
+
==Summary==
  
−
Byte #1: 02 = Techs/Magic
+
Enemy AI is divided into two blocks that terminate with $FF.
−
Byte #2: XX = Attack Type
+
−
Byte #3: Targeting style?
+
−
Byte #4: Double Tech targeting?
+
−
Byte #5: Triple Tech targeting?
+
−
Byte #6: Message
+
  
−
0A XX XX
+
<pre>
 +
AAAAAAAAFF
 +
BBBBBBBBFF
 +
</pre>
  
−
Byte #1: 0A = Disables Enemy
+
The first block contains actions that the enemy performs on its own.
−
XX = Special Attack
+
The second block contains reactions when the enemy is attacked.
−
XX = Message
+
  
−
0B XX XX 00 XX
+
Each block can be broken down into sections that alternate between Condition and Action.
  
−
Byte #1: 0B = Setting Stat
 
−
Byte #2: XX = Stat Type
 
−
Byte #3: XX = Stat set
 
−
Byte #4: 00 = ?
 
−
Byte #5: XX = Message
 
  
−
0C 3D XX XX
+
'''Condition'''
  
−
Byte #1: 0C = Adding Stat
+
Conditions are a multiple of 4 bytes, each of which is a boolean statement.  All must be true for the following Action section to be executed.  The section is terminated by $FE.
−
Byte #2: 3D = Offense
+
−
39 = Magic
+
−
3B = Evade
+
−
38 = Speed
+
−
3E = Defense
+
−
3F = Lightning Defense
+
−
40 = Shadow Defense
+
−
41 = Water Defense
+
−
42 = Fire Defense
+
−
Byte #3: Increment
+
−
Byte #4: Message
+
  
−
0D XX
+
'''Action'''
  
−
0F XX
+
Actions can contain one or more commands to perform.  An enemy's attack meter must refill first before it can continue with the next command.  The section is terminated by $FE.
  
−
Byte #1: 0F = Message Enable
+
==Conditions==
−
Byte #2: XX = Message
+
  
−
Attack/Counterattack Preconditions
+
There is a total of 41 Conditions ($00-28)
−
15 XX = Counters with Type of Attack
+
  
−
20 00 00 00 = Final Attack
+
<pre>xx - unused,
−
17 XX 00 00 = Chances Pattern will be used
+
tt - targeting byte 80 - copy flag, copies $7E:AED8 to $7E:AECC, ignore Targeting 0x7F - targeting routine,
−
1F 04 XX 00 = Distance
+
?? - unknown
−
07 01 00 00 = Custom Pattern is active
+
00 xx xx xx - Default, always passes.
−
11 00 00 00 = Physical Attack
+
01 tt xx xx - HP less than half (tt is usually set to 03 for current enemy,
−
12 XX 01 = Magic Attack
+
              but other values could be used).
−
01 03 = HP is at 50%
+
02 tt oo bb - Check for status. tt - Target, 00 for PCs, 01 for enemies. oo - Offset from
−
05 XX = Number of Monsters in battle
+
              battle data 0x1D (start of status flags). bb - Bits to check.
 +
03 tt mm xx - Checks if something moved. mm - Monster/PC index
 +
04 xx mm ss - Checks status of monster mm - monster index, ss - Status - 00 Alive, 01 - Dead.
 +
05 nn xx xx - Checks for maximum number of living enemies. nn - number of enemies.
 +
06 ff ff ff - Check if battle frame counter is at least ff.
 +
              Value is little endian (lowest byte stored first).
 +
07 vv cc xx - Check custom mode. vv - value, cc - Compare type - 00 >=, 01 <=
 +
08 tt hh hh - Check if HP <= value. hh - HP to compare.
 +
              Value is little endian (lowest byte stored first).
 +
09 tt ss vv - Check if stat is less than value. ss - stat offset. vv - value
 +
0A tt ss bb - Check if stat has bitflags set. ss - stat offset, bb - bitflags set.
 +
0B tt ss vv - Check if stat is less than or equal to value. ss - stat offset, vv - value.
 +
0C tt ff xx - Check if target is inside or outside of a 32 pixel radius. ff - 00 Inside, 01 Outside
 +
0D tt ff xx - Check if X distance against 32 pixels. ff - 00 >, 01 <=
 +
0E tt rr ?? - Distance related. rr - result check mode.
 +
0F tt rr ?? - Distance related. rr - result check mode.
 +
10 xx bb aa - Likely distance related. aa - First calculation switch. bb - Second calculation switch
 +
11 ee xx mm - Check if hit by tech type. ee - 00 player tech, 01 enemy tech. mm - 00 ==, 01 !=
 +
12 ee aa mm - Check if hit by specific tech.  ee - 00 player tech, 01 enemy tech. aa - tech index.
 +
              mm - 00 ==, 01 !=
 +
13 aa xx mm - Check Attacker. aa - 00 player, 01 enemy. mm - 0 ==, 01 !=
 +
14 vv mm ee - Check specific attacker. mm - mode 00 Check attacker against value vv, 01 buggy.
 +
              ee - 00 ==, 01 !=.
 +
              Only checks against player techs and attacks, or enemy techs without enemy vs
 +
              enemy attack set. There is a minor bug in mode 00 when ee is 01. Set 0x019551
 +
              to 89 to fix in the Japanese and US releases.
 +
15 ee xx ff - Checks element of attack, ff - 00 ==, 01 !=, ee - element 20 Ice, 10 Fire,
 +
              80 Lightning, 40 Shadow, 02 Magic, 04 Physical
 +
16 xx xx xx - Copy of 00.
 +
17 pp xx xx - Percent chance. pp - percent
 +
18 vv tt ss - Check if stat is equal. vv - value, ss - stat offset.
 +
19 xx xx xx - Copy of 00.
 +
1A mm aa ss - Check if monster type is alone or not. mm - monster index, aa - 0 - alone,
 +
              1 - with other types.
 +
              ss - If with other types, should the condition succeed? 0 - fail, 1 - succeed.
 +
1B pp xx xx - Count of living PCs is at most pp.
 +
1C tt pp ll - Is PC present or absent. tt can load any targeting routine, but only routines 30-36
 +
              will produce expected results.
 +
              pp - Presence status. 00 - Present, 01 - Absent. ll - Life status. 01 - may be dead.
 +
1D tt xx aa - Check if target is alive or not.
 +
1E xx xx xx - Copy of 00 that sets $7E:AF24 (failure status) to 1 (failed).
 +
1F tt ff xx - Check if target is inside or outside of a 48 pixel radius. ff - 00 Inside, 01 Outside
 +
20 xx xx xx - Final Attack.
 +
21 xx xx xx - $7E:AF15 related.
 +
22 tt ?? cc - $7E:B158 related. cc - compare type 0 - Less than, 1 - Greater than or equal to.
 +
23 vv tt ss - (same as 18)
 +
24 vv tt ss - (same as 18)
 +
25 vv tt ss - (same as 18)
 +
26 vv tt ss - (same as 18)
 +
27 vv tt ss - (same as 18)
 +
28 vv tt ss - (same as 18)</pre>
  
 +
==Actions==
  
 +
There is a total of 23 Actions ($00-16)
  
−
WaddlerD 85: Here's the first bit of attacks that I have found out.
+
<pre>
−
WaddlerD 85: 00 = Flash
+
00 ?? jj ??  wander mode.  jj - multipurpose byte, 80 copy flag: 7EAED8 to 7EAECC, 7F subroutine index
−
01 = Enemy Cure (Target problems, they cure YOU...)
+
01 aa jj ??  attack mode. aa - attack index jj - multipurpose byte, 80 copy flag: 7EAED8 to 7EAECC, 7F subroutine index
−
02 = Lock
+
02 tt jj jj jj ss  tech mode.  tt - tech index jj - multipurpose byte, 80 copy flag: 7EAED8 to 7EAECC, 7F subroutine index ss - battle enemy message string
−
03 = Bird Screech
+
03 (nothing, no routines)
−
04 = Slow Gas Attack
+
04 random action.  uses a random number to determine which action in current section to start on.
−
05 = Nagaette's Slow Spell
+
05 ?? ??  unknown, possibly unused, and not confirmed if it is a 3 byte command.
−
06 = Mune Attack
+
06 (nothing, no routines)
−
07 = Jump n' Land Strike
+
07 mm aa hh  become monster.  mm - monster to turn into aa - animation? hh - hp
−
08 = Sleep Wave
+
08 (nothing, no routines)
−
09 = Dust Breath Attack
+
09 ??  display flashes for distant attack?
−
0A = Fire Breath Attack
+
0A aa ss  run away.  aa - action to show ss - battle enemy message string
−
0B = Grinder Plowing Attack
+
0B oo vv mm ss  set stat.  oo - offset from enemy stat set start vv - value to set/bitwise OR mm - mode, 00 set value 01 bitwise OR ss - battle enemy message string
−
0C = Dragon Tank Missile Salvo
+
0C oo vv ss  stat math.  oo - offset from enemy stat set start vv - multipurpose byte, 80 subtract flag, 7F amount to add/sub ss - battle enemy message string
−
0D = Bubble
+
0D ?? ss  unknown, state change?  ss - battle enemy message string
−
0E = Yakra's Needlespin
+
0E (nothing, no routines)
−
0F = Sleep Bomb
+
0F ss  display text.  ss - battle enemy message string
−
10 = Cybot Singing
+
10 vv ee ss  revive support enemies.  vv - unk. stored to temp 7E000E ee - battle sound effect ss - battle enemy message string
−
11 = Spewing Volcano
+
11 oo vv oo vv oo vv oo vv ss  multi stat set.  oo - offset from enemy stat set start vv - value to set ss - battle enemy message string
−
12 = Rasp
+
12 ?? ?? jj jj oo vv oo vv oo vv oo vv oo vv ss  special multi stat set.  jj - multipurpose byte, 80 copy flag: 7EAED8 to 7EAECC, 7F subroutine index  oo - offset from enemy stat set start vv - value to set ss - battle enemy message string
−
13 = Venomous Gas
+
13 jj vv  unknown, possibly unused, and not confirmed if it is a 3 byte command.  jj - multipurpose byte, 80 copy flag: 7EAED8 to 7EAECC, 7F subroutine index vv - unknown value stored to temp 7E000E
−
14 = Laser Beam
+
14 oo vv oo vv oo vv oo vv ss  multi stat math.  oo - offset from enemy stat set start vv - multipurpose byte, 80 subtract flag, 7F amount to add/sub ss - battle enemy message string
−
15 = Laser Beam Again
+
15 ?? ?? jj jj oo vv oo vv oo vv oo vv oo vv ss  special multi stat math.  jj - multipurpose byte, 80 copy flag: 7EAED8 to 7EAECC, 7F subroutine index oo - offset from enemy stat set start vv - multipurpose byte, 80 subtract flag, 7F amount to add/sub ss - battle enemy message string
−
16 = Missile Salvo
+
16 -- tt oo vv oo vv oo vv oo vv ss  multi revive and set stat.  tt - tech/tech animation related index oo - offset from enemy stat set start vv - value to set ss - battle enemy message string
−
17 = Orb Bomb
+
</pre>
−
18 = Area Bomb
+
−
19 = Amplifire
+
−
1A = Delta Attack
+
−
1B = Ink Blast
+
−
1C = Harmful Gas
+
−
1D = Attack, Attack, Attack/Bugged
+
−
1E = Chaos Bell
+
−
1F = Azala Break
+
−
20 = Yes Indeed!
+
−
21 = Whirlwind Dance/Bugged Alone
+
−
22 = X-Strike/Bugged Alone
+
−
23 = Whirlwind Blast
+
−
24 = Less Hitting Poison Gas
+
−
25 = Fire Trail or Enemy Fire 1
+
−
26 = Pushback Attack
+
−
27 = Static Shock (ALL)
+
−
28 = Static Shock (ONE)
+
−
29 = Shower
+
−
2A = Enemy Ice 1
+
−
2B = Enemy Lightning 1
+
−
2C = Self-Destruct
+
−
2D = Nuke
+
−
2E = Bugged?
+
−
2F = Point Flare
+
  
−
WaddlerD 85: Found out another precondition.
 
  
−
WaddlerD 85: I think 40 00 XX 01 points out "When Monster XX is
+
'''Older data not 100% confirmed:'''
−
dead"
+
−
WaddlerD 85: So if you put 40 00 CF 01 in there, it says "When
+
−
Monster "Bit" is dead", do this.
+
  
−
WaddlerD 85: Ok, should be simple enough.
 
−
WaddlerD 85: You know though...
 
−
WaddlerD 85: There may be something more than what I put down
 
−
for 1F 04 XX XX
 
−
WaddlerD 85: A lot more...
 
  
−
WaddlerD 85: Because Gato has 1F 06 00 00 for his counter attack
+
<pre>
−
precondition...
+
00 WW XX YY            - wander mode YY is how you wander, WW animation related?
−
 
+
02 WW 05 XX YY ZZ      - Spell WW, Message ZZ, XX YY for double/triple?
−
WaddlerD 85: Well, 1F usually deals with distance
+
−
WaddlerD 85: So I guess the three bytes after it have to do with
+
−
something...
+
 
</pre>
 
</pre>
  
−
==Other Findings==
+
==Enemy AI Targeting subroutines==
  
−
''Justin3009''
+
Used by Conditions: 01, 03, 08, 09, 0A, 0B, 0C, 0D, 0E, 0F, 18, 1C*, 1D, 1F, 22, 23-28
 +
Used by Actions: 00, 01, 02, 12, 13, 15
  
−
38910 - Marle Invisible Monster's transform
+
*Condition 1C does not treat the data obtained the from the routines the same way as the others, so it will have unexpected results.
  
−
34341/33345/59108/42312/34523/34112/32198/33333/35312/35464/34921/32421/35353/(44217/45217)(Counter Attack) - Enemy Melee
+
jj - Multiply x2 + 0x01B8BB to obtain the pointer
  
−
45629 - Weird Attack by enemy (almost like golem's)
+
<pre>00 - Nothing
 +
01 - All PCs
 +
02 - All enemies
 +
03 - Current enemy
 +
04 - Attacking PC
 +
05 - Random PC
 +
06 - Nearest PC
 +
07 - Farthest PC
 +
08 - PC with lowest HP. This routine does not properly check PC1's HP. To fix, replace 0x01A50C (unheadered US or Japanese ROM) with D0 05 EA EA.
 +
09 - PCs with any flags on battle data 0x1D set. 80 is used for a dead PC, others are unknown.
 +
0A - PCs with any negative status.
 +
0B - PCs with any flags on battle data 0x1F (unknown)
 +
0C - PCs with any positive status from set 1 (2x Evade/Unknown Status/2.5x Evade/Haste)
 +
0D - PCs with any positive status from set 2 (Attack Power Up/Shield (Defense Up)/Max Attack Power Up/MP Regen/Barrier (M. Defense Up)/Berserk)
 +
0E - Sleeping PCs
 +
0F - Stopped PCs
 +
10 - Confused PCs
 +
11 - Shielded (Defense Up) PCs
 +
12 - Barriered (M. Defense Up) PCs
 +
13 - PCs with bit 10 of positive status set 2 (unused)
 +
14 - PCs with bit 8 of battle data 01 (unknown)
 +
15 - Other enemies
 +
16 - Living enemies
 +
17 - Nearest enemy
 +
18 - Farthest enemy
 +
19 - Enemy with lowest HP
 +
1A - Other enemies with any battle data 0x1D flags set
 +
1B - All enemies with any battle data 0x1D flags set
 +
1C - Other enemies with any negative status
 +
1D - All enemies with any negative status
 +
1E - Other enemies with any flags on battle data 0x1F (unknown)
 +
1F - All enemies with any flags on battle data 0x1F (unknown)
 +
20 - Other Sleeping enemies
 +
21 - Other Stopped enemies
 +
22 - Other Confused enemies
 +
23 - Other Barriered (M. Defense Up) enemies
 +
24 - Other enemies with 0x1D bitflag 2 set
 +
25 - Other enemies with 0x19 bitflag 1 set
 +
26 - Enemy with lowest HP other than self
 +
27 - Enemy 03. This and the following routines are mostly used with multi-part bosses. Enemy index is determined by event commands.
 +
28 - Enemy 04
 +
29 - Enemy 05
 +
2A - Enemy 06
 +
2B - Enemy 07
 +
2C - Enemy 08
 +
2D - Enemy 09
 +
2E - Enemy 0A
 +
2F - Random enemy with $7E:AF15 bit 80 set
 +
30 - PC 1. This and the following routines were most likely designed for condition 1C, check for specific PC. If used in that condition, it would check for Crono.
 +
31 - PC 2
 +
32 - PC 3
 +
33 - Enemy 3
 +
34 - Enemy 4
 +
35 - Enemy 5
 +
36 - Enemy 6
 +
37 - PC with highest HP
 +
38 - Random enemy other than self</pre>
  
−
43212 - Robot/Dragon Tank Moves?
+
==Supplemental Material==
 +
*[[EnemyAI Old]]
 +
*[[Enemy AI_Listings]]
  
−
46645/43217 - robot move
 
−
 
−
54332 - Span Death/ Arm Revives Body (Kills Hero and 2 Enemies)
 
−
 
−
54512/54651/54325 - Barrier Change Message Repeating
 
−
 
−
56654 - Hexagon Mist/Water Message Repeating
 
−
 
−
45333 - Zeal (Hands/Head Moves)
 
−
 
−
51652 - (Magus Moves)
 
−
 
−
42217 - Low Life
 
−
 
−
48217 - Automatic Win
 
−
 
−
59217 - Area Change?/Hero's Attack Themselves?
 
−
 
−
52217 - Area Bomb Message Appears
 
−
 
−
12341/12741 - Strange Win?
 
−
 
−
23411/15297/59231/12347/23409/23421/958/951/14512 - Freezes Game
 
−
 
−
43123 - Copy Cat Ability/Copies Phycics message repeating
 
−
 
−
38764 - 1 hit win
 
−
 
−
42978 - Dragon Tank
 
−
 
−
55789/54129/54213/53451/54643/53750 - Barrier Change Message Repeating
 
−
 
−
49876/50000 - Unfinished Double techs
 
−
 
−
29873 - Gaia Magnade/Fire Message Repeating
 
−
 
−
39065 - Absorbs More Elemental Damage
 
−
 
−
19824/24312 - Slows Game
 
−
 
−
48971 - Strange Effects...
 
−
 
−
49441 - The Parts on the Right Store Energy...Message Repeating
 
−
 
−
43298/43291 - Automatic win/Apart Masa and Mune Are Powerless Msg..
 
−
 
−
42831 - 1 Yakra Move
 
−
 
−
12478 - Double Part Attack/Dark Plasma Message Repeating
 
−
 
−
45123 - hero takes over enemy
 
−
 
−
42312/38312(Close Range) - Enemy Steals Life
 
−
 
−
12973 - Defense Down Message Appears and Freezes Game
 
−
 
−
47819 - Dragon Tank Missles
 
−
 
−
5309 - Grand Stone/ Ultimnate physical attack (Freezes game)
 
−
 
−
61470 - Dark Gear/ Shadow Message Repeating
 
−
 
−
40395 - Enemy Uses weird move (Screen turns red and rocks fall)
 
−
 
−
24341 - Either Slows game or Slows Battle Stances
 
−
 
−
45432 - Counter Attack/ Life Shaver
 
−
 
−
51312 - Counter Attack: Flare
 
−
 
−
52312 - Gives weird mana drains all items and Barrier Change/Ding-Aling-Chaos message
 
−
 
−
49312 - Lavos Moves/Yakra Move?
 
−
 
−
47312 - Steals life/ Shakes the Ground/Tornado Energy Neutralized message
 
−
 
−
44312 - Destroy's Graphics/ Bad Impulse ---- (Couldn't read rest of message)
 
−
 
−
43312 - Attacks Hero, but when attacked, Apart Masa and Mune Are Powerless (Ends Battle)
 
−
 
−
36312 - Shoots a Bunch of Flames
 
−
 
−
51112 - Area Bomb on Enemy
 
−
 
−
51012 - Go ahead...Try and attack (Shoot's Flame)
 
−
 
−
51002 - Lavos Core is Defended! (Shoot's Flame)
 
−
 
−
51119 - Area Bomb On Hero's
 
−
 
−
51149 - Golem Boss Run Away Move
 
−
 
−
56512 - Removes third party menu over and over
 
−
 
−
34523 - Walk Around and Attack
 
−
 
−
57298/12451/41931 - destroys graphics (does many things)
 
−
 
−
32489 - Freezes game
 
−
 
−
40000 - Shoots Laser
 
−
 
−
47800 - Shoots Missles
 
−
 
−
57212 - Hero's attack themselves and Reprogramming/Chaos Message Appears
 
−
 
−
57212 - Hero's attack themselves and Reprogramming/Chaos Message Appears
 
−
 
−
3561 - Span Death/Arm Revives Main Body.. Message Repeats
 
−
 
−
10294 - After any attack game screen goes black and dissappears
 
−
 
−
9931 - Kills enemy after 3 turns and constantly plays enemy death sound then game freezes
 
−
 
−
16528/15460 - Enemy tries to run then game freezes
 
−
 
−
13256 - Attack/will attack with no center bit.
 
−
 
−
15555 - Double-Part Attack/Dark-Plasma
 
−
 
−
43216 - Copy Cat Ability/Copies Phycics message repeating (Does Missle Attack, Laser Beam, and Time Stop)
 
−
 
−
49216 - Blue scout fights all mag but "water".
 
−
 
−
46216 - Eats hero for life and uses some strange fire attack that hits everything
 
−
 
−
10896 - 1st person in slot shakes head and game freezes
 
−
 
−
59230 - Lavos Core is Defended! message repeats
 
−
 
−
42190 - Makes game skippy
 
−
 
−
42956 - Shoots yellow laser beam
 
−
 
−
43956 - Slashes's Attacks
 
−
 
−
45956 - Robo's Heal Beam?
 
−
 
−
47956 - Missles
 
−
 
−
50956 - Lavos Bit Attacks?
 
−
 
−
51956 - Fire 2, Lightning 2, Ice 2
 
−
 
−
57956 - Js theot ththingver: Th Message appears (automatic win) But drains life
 
−
 
−
61956 - Mutant Gas/Poison Message Repeats
 
−
 
−
39956 - Blue scout fights all mag but "lightning". Then does MP Buster
 
−
 
−
37956 - Shoots Dirt at Heroes and Melee attacks
 
−
 
−
16956 - Napalm Message Repeats (hero Attacks enemy but then attacks a hero)
 
−
 
−
12956 - Shadow Slay Message Repeats
 
−
 
−
5956 - Freeze/stop message repeats
 
−
 
−
61258 - ♪-- ♪- ♪♪--/chaos message repeats
 
−
 
−
45874 - Sand Breath/Darkness (Def powered up when attack) Steals Life
 
−
 
−
41874 - If hero attack Enemy runs away (Attack pwr up) Message repeats
 
−
 
−
39874 - 10,000 Hz/sleep strike from the heavens above
 
−
 
−
38874 - Physical defense on If attacked Magical Defense on if Magic
 
−
 
−
37874 - If attacked does hallation
 
−
 
−
36874 - If attacked uses Cure 2?
 
−
 
−
40874 - Does slash and slow
 
−
 
−
24874 - Crying Heavens/Hidden Below message repeats
 
−
 
−
16874 - Double-Part Attack/Dark-Plasma Message repeats If hero lands a strike, Hero attacks him/herself
 
−
 
−
15874 - Obstacle message repeats
 
−
 
−
11523 - Counter-Attack
 
−
 
−
10523 - Plays enemy death sound when enemy is defeated over and over. Then says destruction zone, screws up the graphics, anything other then that turns into a robot laser.
 
−
 
−
9523 - Plays enemy death sound when enemy is defeated over and over. Then says Mortal Blow, screws up the graphics, anything other then that turns into a robot laser.
 
−
 
−
45523 - Doom, Doom Doom Doom... - Screws up Graphics and does some odd attack.
 
−
 
−
59632 - Attacks enemy then shakes head left to right
 
−
 
−
10203 - hero dissappears enemy dissappears turns into a "nu" or so they say and screws up graphics on hero
 
−
 
−
50314 - Shoots flames and eats hero
 
−
 
−
13620 - Counter attacks during battle message repeats
 
−
 
−
60340 - Pain... Message appears at the beginning of the battle
 
−
 
−
32056 - Counter-Attacks
 
−
 
−
16450 - Life Shaver/ Hp goes to 1 - If successful hit hero attacks themselves and takes no dmg
 
−
 
−
63190 - Waltz of the wind (insert heart symbol here)/chaos
 
−
 
−
40210 - Barghest's shield destroyed... message appears after the first attack
 
−
 
−
 
−
''Chickenlump''
 
−
<pre>
 
−
09 XX
 
−
XX = Attack to use
 
−
 
−
These attacks do absolutely no damage (not even 0), but the attack effect plays out. I've seen these in 2 unnamed monster's scripts (lavos support monsters I think, they have no name, #'s B5 and B6).
 
−
 
−
28 XX YY  - Change Stats
 
−
XX - Stat to change
 
−
YY - Amount to change
 
−
 
−
You can change HP, MP, wounded, etc. stats of characters with this one.</pre>
 
−
 
−
''Vehek''
 
−
<pre>
 
−
07 XX YY ZZ - Become different monster
 
−
XX - Type of monster to become
 
−
YY - Attack animation to use. (So far, only 70 and 7D have been tested and shown to update the name and sprite.)
 
−
ZZ - Haven't really investigated; affects whether it keeps its current HP when it changes.
 
−
This requires the location events to be set up in a certain way.
 
−
</pre>
 
 
''From'': [[Offsets (Chrono Trigger)]]
 
''From'': [[Offsets (Chrono Trigger)]]

Revision as of 22:54, 13 November 2017

Notes on Enemy AI are currently incomplete; eventually, data will be decoded and added into Temporal Flux for functionality. Enemy AI information will be updated as new stuff comes.

Offsets

Directly from Geiger's Offsets.txt
___________________________________________________________________
0C8B08 0C8D07 PTR No No Pointers to Enemy AI (local) 6/21/2004
0C8D08 0CCBC8 AI No No Enemy AI 7/14/2003
___________________________________________________________________



Summary

Enemy AI is divided into two blocks that terminate with $FF. 

AAAAAAAAFF
BBBBBBBBFF

The first block contains actions that the enemy performs on its own. The second block contains reactions when the enemy is attacked.

Each block can be broken down into sections that alternate between Condition and Action.


Condition

Conditions are a multiple of 4 bytes, each of which is a boolean statement. All must be true for the following Action section to be executed. The section is terminated by $FE.

Action

Actions can contain one or more commands to perform. An enemy's attack meter must refill first before it can continue with the next command. The section is terminated by $FE.

Conditions

There is a total of 41 Conditions ($00-28) 

xx - unused, 
tt - targeting byte 80 - copy flag, copies $7E:AED8 to $7E:AECC, ignore Targeting 0x7F - targeting routine, 
?? - unknown
00 xx xx xx - Default, always passes.
01 tt xx xx - HP less than half (tt is usually set to 03 for current enemy, 
              but other values could be used).
02 tt oo bb - Check for status. tt - Target, 00 for PCs, 01 for enemies. oo - Offset from 
              battle data 0x1D (start of status flags). bb - Bits to check.
03 tt mm xx - Checks if something moved. mm - Monster/PC index
04 xx mm ss - Checks status of monster mm - monster index, ss - Status - 00 Alive, 01 - Dead.
05 nn xx xx - Checks for maximum number of living enemies. nn - number of enemies.
06 ff ff ff - Check if battle frame counter is at least ff. 
              Value is little endian (lowest byte stored first).
07 vv cc xx - Check custom mode. vv - value, cc - Compare type - 00 >=, 01 <=
08 tt hh hh - Check if HP <= value. hh - HP to compare. 
              Value is little endian (lowest byte stored first).
09 tt ss vv - Check if stat is less than value. ss - stat offset. vv - value
0A tt ss bb - Check if stat has bitflags set. ss - stat offset, bb - bitflags set.
0B tt ss vv - Check if stat is less than or equal to value. ss - stat offset, vv - value.
0C tt ff xx - Check if target is inside or outside of a 32 pixel radius. ff - 00 Inside, 01 Outside
0D tt ff xx - Check if X distance against 32 pixels. ff - 00 >, 01 <=
0E tt rr ?? - Distance related. rr - result check mode.
0F tt rr ?? - Distance related. rr - result check mode.
10 xx bb aa - Likely distance related. aa - First calculation switch. bb - Second calculation switch
11 ee xx mm - Check if hit by tech type. ee - 00 player tech, 01 enemy tech. mm - 00 ==, 01 !=
12 ee aa mm - Check if hit by specific tech.  ee - 00 player tech, 01 enemy tech. aa - tech index. 
              mm - 00 ==, 01 !=
13 aa xx mm - Check Attacker. aa - 00 player, 01 enemy. mm - 0 ==, 01 !=
14 vv mm ee - Check specific attacker. mm - mode 00 Check attacker against value vv, 01 buggy. 
              ee - 00 ==, 01 !=. 
              Only checks against player techs and attacks, or enemy techs without enemy vs 
              enemy attack set. There is a minor bug in mode 00 when ee is 01. Set 0x019551 
              to 89 to fix in the Japanese and US releases.
15 ee xx ff - Checks element of attack, ff - 00 ==, 01 !=, ee - element 20 Ice, 10 Fire, 
              80 Lightning, 40 Shadow, 02 Magic, 04 Physical
16 xx xx xx - Copy of 00.
17 pp xx xx - Percent chance. pp - percent
18 vv tt ss - Check if stat is equal. vv - value, ss - stat offset.
19 xx xx xx - Copy of 00.
1A mm aa ss - Check if monster type is alone or not. mm - monster index, aa - 0 - alone, 
              1 - with other types. 
              ss - If with other types, should the condition succeed? 0 - fail, 1 - succeed.
1B pp xx xx - Count of living PCs is at most pp.
1C tt pp ll - Is PC present or absent. tt can load any targeting routine, but only routines 30-36 
              will produce expected results. 
              pp - Presence status. 00 - Present, 01 - Absent. ll - Life status. 01 - may be dead.
1D tt xx aa - Check if target is alive or not.
1E xx xx xx - Copy of 00 that sets $7E:AF24 (failure status) to 1 (failed).
1F tt ff xx - Check if target is inside or outside of a 48 pixel radius. ff - 00 Inside, 01 Outside
20 xx xx xx - Final Attack.
21 xx xx xx - $7E:AF15 related.
22 tt ?? cc - $7E:B158 related. cc - compare type 0 - Less than, 1 - Greater than or equal to.
23 vv tt ss - (same as 18)
24 vv tt ss - (same as 18)
25 vv tt ss - (same as 18)
26 vv tt ss - (same as 18)
27 vv tt ss - (same as 18)
28 vv tt ss - (same as 18)

Actions

There is a total of 23 Actions ($00-16) 

00 ?? jj ??  wander mode.  jj - multipurpose byte, 80 copy flag: 7EAED8 to 7EAECC, 7F subroutine index
01 aa jj ??  attack mode.  aa - attack index jj - multipurpose byte, 80 copy flag: 7EAED8 to 7EAECC, 7F subroutine index
02 tt jj jj jj ss  tech mode.  tt - tech index jj - multipurpose byte, 80 copy flag: 7EAED8 to 7EAECC, 7F subroutine index ss - battle enemy message string
03 (nothing, no routines)
04  random action.  uses a random number to determine which action in current section to start on.
05 ?? ??  unknown, possibly unused, and not confirmed if it is a 3 byte command.
06 (nothing, no routines)
07 mm aa hh  become monster.  mm - monster to turn into aa - animation? hh - hp
08 (nothing, no routines)
09 ??  display flashes for distant attack?
0A aa ss  run away.  aa - action to show ss - battle enemy message string
0B oo vv mm ss  set stat.  oo - offset from enemy stat set start vv - value to set/bitwise OR mm - mode, 00 set value 01 bitwise OR ss - battle enemy message string
0C oo vv ss  stat math.  oo - offset from enemy stat set start vv - multipurpose byte, 80 subtract flag, 7F amount to add/sub ss - battle enemy message string
0D ?? ss  unknown, state change?  ss - battle enemy message string
0E (nothing, no routines)
0F ss  display text.  ss - battle enemy message string
10 vv ee ss  revive support enemies.  vv - unk. stored to temp 7E000E ee - battle sound effect ss - battle enemy message string
11 oo vv oo vv oo vv oo vv ss  multi stat set.  oo - offset from enemy stat set start vv - value to set ss - battle enemy message string
12 ?? ?? jj jj oo vv oo vv oo vv oo vv oo vv ss  special multi stat set.  jj - multipurpose byte, 80 copy flag: 7EAED8 to 7EAECC, 7F subroutine index  oo - offset from enemy stat set start vv - value to set ss - battle enemy message string
13 jj vv  unknown, possibly unused, and not confirmed if it is a 3 byte command.  jj - multipurpose byte, 80 copy flag: 7EAED8 to 7EAECC, 7F subroutine index vv - unknown value stored to temp 7E000E
14 oo vv oo vv oo vv oo vv ss  multi stat math.  oo - offset from enemy stat set start vv - multipurpose byte, 80 subtract flag, 7F amount to add/sub ss - battle enemy message string
15 ?? ?? jj jj oo vv oo vv oo vv oo vv oo vv ss  special multi stat math.  jj - multipurpose byte, 80 copy flag: 7EAED8 to 7EAECC, 7F subroutine index oo - offset from enemy stat set start vv - multipurpose byte, 80 subtract flag, 7F amount to add/sub ss - battle enemy message string
16 -- tt oo vv oo vv oo vv oo vv ss  multi revive and set stat.  tt - tech/tech animation related index oo - offset from enemy stat set start vv - value to set ss - battle enemy message string


Older data not 100% confirmed: 


00 WW XX YY            - wander mode YY is how you wander, WW animation related?
02 WW 05 XX YY ZZ      - Spell WW, Message ZZ, XX YY for double/triple?

Enemy AI Targeting subroutines

Used by Conditions: 01, 03, 08, 09, 0A, 0B, 0C, 0D, 0E, 0F, 18, 1C*, 1D, 1F, 22, 23-28 Used by Actions: 00, 01, 02, 12, 13, 15

  • Condition 1C does not treat the data obtained the from the routines the same way as the others, so it will have unexpected results.

jj - Multiply x2 + 0x01B8BB to obtain the pointer 

00 - Nothing
01 - All PCs
02 - All enemies
03 - Current enemy
04 - Attacking PC
05 - Random PC
06 - Nearest PC
07 - Farthest PC
08 - PC with lowest HP. This routine does not properly check PC1's HP. To fix, replace 0x01A50C (unheadered US or Japanese ROM) with D0 05 EA EA.
09 - PCs with any flags on battle data 0x1D set. 80 is used for a dead PC, others are unknown.
0A - PCs with any negative status.
0B - PCs with any flags on battle data 0x1F (unknown)
0C - PCs with any positive status from set 1 (2x Evade/Unknown Status/2.5x Evade/Haste)
0D - PCs with any positive status from set 2 (Attack Power Up/Shield (Defense Up)/Max Attack Power Up/MP Regen/Barrier (M. Defense Up)/Berserk)
0E - Sleeping PCs
0F - Stopped PCs
10 - Confused PCs
11 - Shielded (Defense Up) PCs
12 - Barriered (M. Defense Up) PCs
13 - PCs with bit 10 of positive status set 2 (unused)
14 - PCs with bit 8 of battle data 01 (unknown)
15 - Other enemies
16 - Living enemies
17 - Nearest enemy
18 - Farthest enemy
19 - Enemy with lowest HP
1A - Other enemies with any battle data 0x1D flags set
1B - All enemies with any battle data 0x1D flags set
1C - Other enemies with any negative status
1D - All enemies with any negative status
1E - Other enemies with any flags on battle data 0x1F (unknown)
1F - All enemies with any flags on battle data 0x1F (unknown)
20 - Other Sleeping enemies
21 - Other Stopped enemies
22 - Other Confused enemies
23 - Other Barriered (M. Defense Up) enemies
24 - Other enemies with 0x1D bitflag 2 set
25 - Other enemies with 0x19 bitflag 1 set
26 - Enemy with lowest HP other than self
27 - Enemy 03. This and the following routines are mostly used with multi-part bosses. Enemy index is determined by event commands.
28 - Enemy 04
29 - Enemy 05
2A - Enemy 06
2B - Enemy 07
2C - Enemy 08
2D - Enemy 09
2E - Enemy 0A
2F - Random enemy with $7E:AF15 bit 80 set
30 - PC 1. This and the following routines were most likely designed for condition 1C, check for specific PC. If used in that condition, it would check for Crono.
31 - PC 2
32 - PC 3
33 - Enemy 3
34 - Enemy 4
35 - Enemy 5
36 - Enemy 6
37 - PC with highest HP
38 - Random enemy other than self

Supplemental Material

From: Offsets (Chrono Trigger)

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