A ROM hack for Mickey Mousecapade (NES, 1987) that adds genuine simultaneous two-player co-op. Player 2 controls Minnie.
Mickey Mousecapade is built around two characters but only ever had room for one player: Minnie follows Mickey under CPU control, and controller 2 does nothing. This hack hands her to a second player — her own movement, jumping, swimming, doors, item pickups, and her own star shots.
- Simultaneous two-player co-op; Minnie is fully player-controlled
- Title-screen mode select (ONE PLAYER / TWO PLAYER) with a star cursor and menu SFX
- Faithful one-player mode — every change is gated on the selected mode, so 1P keeps the original follow AI, owl kidnapping, and behaviour
- Each character shoots with their own B button in two-player
- Exactly one background tile differs from the original ROM (the cursor star)
- Mapper 3 / CNROM, no expansion hardware — runs on real hardware
- The patching hashes in the README are for the base ROM, so they stay correct as-is.
Apply the .bps to an unmodified USA ROM with the 16-byte iNES header:
| No-Intro | Mickey Mousecapade (USA).nes |
| Size | 65,552 bytes (65,536 + 16-byte header) |
| CRC32 | 1D961110 |
| MD5 | D634A9B11B464BC2A6C452BAF5A57F3E |
| SHA-1 | C37AA6ACFCD64EB51E93E77881BABC8C06779BEE |
Use Flips, beat, or
Rom Patcher JS. The BPS verifies the ROM's
checksum and refuses the wrong file. An .ips is included for legacy patchers
only — it has no checksum, and applied to a headerless ROM it will silently
produce a broken game.
No ROM is distributed here. Supply your own.
The hack is assembled by a Python toolchain rather than a hex editor:
| File | Purpose |
|---|---|
build_patch_v41.py |
Applies site patches + code blobs, emits the ROM and IPS |
v41_gates.py |
6502 gate routines, hook table, free-space map |
test_gates_v41.py |
27 unit tests for the mode gates |
nes_fast.py |
Headless 6502 harness (exec-compiled opcode handlers) |
audit_tiles.py |
CNROM+PPU shim; runs the real screen loaders and records every tile written to a nametable |
make_bps.py |
BPS patch creation + verification |
Every mode-dependent change is a gate: a small routine that reads the mode
byte at $07FF and either runs the vanilla code path or the two-player one.
That is what keeps ONE PLAYER byte-faithful to the original game.
Hack, disassembly and tooling by SideofClouds. Mickey Mousecapade © 1987 Hudson Soft / Capcom.