| Field | Value |
|---|---|
| Patch file | mk64_eu_battle_curve.ips |
| Base ROM | Mario Kart 64 (Europe) PAL (extracted from Wii WAD) |
| ROM size | 12 MB (12,582,912 bytes) |
| Apply with | Lunar IPS, RomPatcher.js, UniPatcher |
Modifies the battle mode item probability curve stored in the common data MIO0-compressed block (ROM 0x132C70, segment offset 0x8B14). The 100-slot item table determines the likelihood of each item appearing from an item box.
| ID | Item | Vanilla | Patched | Change |
|---|---|---|---|---|
01 |
Single Banana | 10% | 10% | — |
02 |
Banana Bunch | 5% | 5% | — |
03 |
Single Green Shell | 5% | 10% | +5% |
04 |
Triple Green Shell | 20% | 21% | +1% |
05 |
Single Red Shell | 20% | 16% | −4% |
06 |
Triple Red Shell | 0% | 10% | ✅ added |
08 |
Lightning | 0% | 3% | ✅ added (rare) |
09 |
Fake Item Box | 15% | 10% | −5% |
0A |
Invincible Star | 20% | 10% | −10% |
0B |
Ghost | 5% | 5% | — |
| Field | Value |
|---|---|
| Patch file | mk64_eu_blitz_squish_balloon.ips — lightning change only |
| Complete patch | mk64_eu_battle_v2_komplett.ips — item curve + lightning, apply to a clean EU ROM |
| Result ROM | rom_battle_v2.z64 — curve + lightning, ready to play (CRC recalculated) |
| Note | rom_blitz_squish.z64 contains ONLY the lightning patch (no item curve), can be deleted |
Before: Lightning in battle mode → all opponents immediately lose a balloon and shrink. After: Lightning only shrinks. The balloon is lost only when the shrunken opponent gets run over (squished).
| Location | ROM | RAM | Change |
|---|---|---|---|
trigger_lightning_strike: jal pop_player_balloon |
0x8ECDC | 0x8008E0DC | → nop (no immediate balloon loss) |
apply_lightning_effect: jal trigger_squish |
0x8EDA0 | 0x8008E1A0 | → jal 0x8008C298 (hook) |
| Code cave (empty UNUSED functions) | 0x8CE98 | 0x8008C298 | if gModeSelection==3 (battle): pop_player_balloon(player, idx), then always trigger_squish(player, idx) |
Key symbols (EU v1.1):
| Symbol | RAM |
|---|---|
pop_player_balloon |
0x8006B894 (ROM 0x6C494) |
trigger_squish |
0x8008DA9C (ROM 0x8E69C) |
apply_lightning_effect |
0x8008E0F8 (ROM 0x8ECF8) |
gModeSelection |
0x800DC55C (3 = battle) |
gPlayerBalloonCount[8] (s16) |
0x8018D920 |
Bugfix history: v1 of the patch jumped to 0x8008C27C (delta incorrectly determined as 0x7FFFF3E4, because IDO schedules instructions before the addiu sp in pop_player_balloon) → the hook landed on a bare jr ra, so squish/balloon loss never ran. Correct: delta 0x7FFFF400.
Note: The header CRC was not recalculated (the Wii VC ROM has no standard CRC anyway; emulators don't check it).
| Field | Value |
|---|---|
| Patch file | mk64_eu_shrink_timer_30s.ips — apply on top of rom_battle_v2.z64 |
| Complete patch | mk64_eu_battle_v3_komplett.ips — item curve + lightning + timer, apply to a clean EU ROM |
| Result ROM | rom_battle_v3.z64 — everything included, ready to play (CRC recalculated: B5ADCEF9 F73D28E9) |
The shrunken state after a lightning strike lasts 1500 frames instead of 460 (0x5DC instead of 0x1CC) — about 30 seconds. Live testing showed the timer ticks at ~50/s (PAL vsync rate), not at the logic frame rate: 750 frames measured ~15-16 s, so 1500 ≈ 30 s. Vanilla: 460 ≈ 9 s.
| Location | ROM | RAM | Change |
|---|---|---|---|
apply_lightning_effect: slti $at, $v0, 0x1CC |
0x8EEE0 | 0x8008E2E0 | immediate 0x1CC → 0x5DC (460 → 1500 frames) |
The timer is player + 0xB0 (s16): set to 0 on lightning strike (0x8008DFF4), incremented once per frame (0x8008E280), compared against the limit at 0x8008E2E0. Once the limit is reached, the grow-back path (0x8008E348) runs. This is the only comparison against 0x1CC in the code — same duration for all players.
To verify the actual tick rate live: watch player + 0xB0 and time how fast it counts.