Shippu Mahou Daisakusen/Reverse engineering notes
TODO: clean up addresses below pointing directly to bytes when code is operating on them as words. e.g., P1 lives @ 100555.b is probably referenced in the code as 100554.w
- 1006C6 - seems to consistently hold boss HP value when one is on screen
- 1006AA - base address of the boss enemy object
- object+$04 - animation frame
- object+$06 - animation related flags (sprite rotation, hit flash and/or palette?, etc.)
- object+$08 - y-coord
- object+$0A - x-coord
- object+$1C - HP value for enemies. Damage value for projectiles/player, to apply against target enemy up to their specified durability cap
- object+$36 - i-frames
- Code @ 13D78 - damage calculation for durable enemies
- Code @ 13F6A - damage calculation for zakos (uncapped)
- 100551 - current play state?
- 100553 - current play flags?
- 100555 - current P1 lives
- 10055c - current P1 character
10055c character values:
| Gain | Chitta | Miyamoto | Bornnam | Nirvana | Kickle & Laycle | Honest John | Bul-Gin |
|---|---|---|---|---|---|---|---|
| 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 |
- 10058C = current calculated rank
- 10058E = base rank for current stage
- 100590 = survival rank (resets on stage start or player death)
- 1006A4 = survival rank increment timer (does not reset on stage start)
- 102C4A + $44 (102C8E) = maximum unboosted speed
- 102C4A + $46 (102C90) = minimum unboosted speed
- 102C4A + $22 (102c6c) = current speed
- 1012DE = P1 main shot power
- 1012D6 = P1 bomb count
- 1012DA = P1 sub-weapon type
- 1012D8 = P1 sub-weapon power
- 1005B1 - current stage
- 1005B3 - current track
- 1005B5 - current loop (0 = first, 1 = second)
- 100656 - table of P1 track times
- 10066E - table of track selections
Speed and Boost Mechanics
(To be pared down and moved elsewhere later; some of this can probably go on the main page, or a racing-focused subpage)
These are the maximum and minimum unboosted speed values for each track (obtained by observing 102C8E and 102C90 while playing the game). Some short sections are omitted (for example, when the wave of water comes in Deeply Dungeon, max and min speed are both briefly set to 1024).
| Track | Min | Max |
|---|---|---|
| Basalna City | 256 | 512 |
| Air Circus | 384 | 640 |
| Air Circus (Boss) | 256 | 512 |
| Velmatic Ocean | 256 | 512 |
| Outcast Castle | 128 | 256 |
| Outcast Castle (Worms) | 64 | 192 |
| Outcast Castle (After Boss) | 256 | 512 |
| Cross Fire | 512 | 1024 |
| Deeply Dungeon | 96 | 192 |
| Deeply Dungeon (Boss) | 160 | 224 |
| Deeply Dungeon (After Boss) | 160 | 320 |
| Cold Corridor | 256 | 512 |
| Cold Corridor (Boss) | 192 | 256 |
| Cold Corridor (After Boss) | 192 | 512 |
| Strato Storm | 640 | 1280 |
| Forest of Dead! | 192 | 384 |
| Forest of Dead! (After Boss) | 256 | 512 |
| Kingdom Grandprix | 512 | 768 |
| Yashiki of Ninja | 128 | 256 |
| Yashiki of Ninja (After Boss) | 256 | 512 |
| Kobolds Tower | 192 | 384 |
| Kobolds Tower (Rocks) | 128 | 256 |
Boosting increases your speed beyond the unboosted maximum by up to 128 units, regardless of stage. This means boosting has a more significant effect on slow stages. For example, on Strato Storm, boosting can only increase your speed by up to 110%, while in Outcast Castle, it can increase your speed by up to 150% (early on) or ~167% (worm section).
Whether the maximum boost of +128 is actually reachable depends on three factors:
- Per-character per-stage base boost speed (see table below)
- Main shot power bonus (grants a small bonus for each power level)
- Bomb count modifier (grants a bonus for less than 4 bombs, or a penalty for more than 4 bombs)
The extra speed from boosting is calculated by adding together the values from the following tables. If the value exceeds 128, it is capped at 128.
As an example, Chitta has a base boost speed of 48 on Air Circus. If she has full shot power, she gets a +6 bonus, and if she has the default 3 bombs, she gets a +8 bonus. This means boosting on Air Circus will only increase her speed by 48 + 6 + 8 = 62 units. Even if Chitta use all her bombs to get the +32 bomb count bonus, that only gets her to 86 units. In general, if a character's base boost speed is lower than 96, they can't reach the maximum boost of 128 for that stage.
Base Boost Speed (depends on stage and character)
| Track | Gain | Chitta | Miyamoto | Bornnam | Nirvana | Kickle & Laycle | Honest John | Bul-Gin |
|---|---|---|---|---|---|---|---|---|
| Basalna City | 96 | 96 | 96 | 96 | 96 | 96 | 96 | 96 |
| Air Circus | 128 | 48 | 96 | 32 | 80 | 128 | 112 | 64 |
| Velmatic Ocean | 80 | 128 | 96 | 64 | 128 | 48 | 32 | 80 |
| Outcast Castle | 80 | 64 | 128 | 128 | 96 | 48 | 112 | 32 |
| Cross Fire | 128 | 112 | 32 | 80 | 48 | 96 | 64 | 128 |
| Deeply Dungeon | 32 | 112 | 96 | 128 | 80 | 128 | 48 | 64 |
| Cold Corridor | 64 | 128 | 48 | 96 | 32 | 80 | 128 | 112 |
| Strato Storm | 96 | 32 | 80 | 80 | 128 | 64 | 112 | 128 |
| Forest of Dead! | 80 | 64 | 112 | 128 | 96 | 32 | 128 | 48 |
| Kingdom Grandprix | 128 | 96 | 96 | 96 | 112 | 128 | 128 | 112 |
| Yashiki of Ninja | 112 | 128 | 128 | 128 | 96 | 112 | 112 | 96 |
| Kobolds Tower | 96 | 112 | 128 | 112 | 128 | 96 | 96 | 128 |
Main Shot Power Bonus
| Level 0 | Level 1 | Level 2 | Level 3 |
|---|---|---|---|
| 0 | +2 | +4 | +6 |
Bomb Count Modifier
| 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7+ |
|---|---|---|---|---|---|---|---|
| +32 | +24 | +16 | +8 | 0 | -8 | -16 | -32 |
The relevant routines are at 7AD6 and 174D0. The routine at 7AD6 reads from a table stored at 718C2, which contains the base boost speed values for each character and stage. The routine at 174D0 applies the main shot power bonus and the bomb count modifier, using tables stored at 17568 (shot power bonus) and 175AE (bomb count modifier). This routine also seems to do some stuff related to subweapons (probably damage calculations?) and there's a big table of subweapon-related values at 1756E.
