Missingno is an emulator for the Game Boy, Game Boy Color, Atari VCS (2600), Sega SG-1000, and ColecoVision. It is built around faithful models of the original hardware: games look, sound, and behave as they do on the real machines, with display options that recreate the look of the original LCD and CRT screens.
The library manages your collection: cover art and metadata are fetched automatically, play sessions and screenshots are recorded, and saves are managed and backed up. Homebrew games can be browsed and downloaded from Homebrew Hub, and physical cartridges read and written with a GBxCart RW.
The integrated debugger works across every supported system, with disassembly, breakpoints, and live inspection of CPU, video, and audio state.
Screenshots
Observed history
| App | Change | Version | When ↓ |
|---|---|---|---|
| updated | 26.10 | 2 Oct 2026 |
Upstream releases
Release notes supplied by the developer. These dates are not Flathub package publication times.
26.103 Oct 2026
- ColecoVision support
- PAL Sega SG-1000 consoles
- Console firmware (BIOS and boot ROM) selection
- Minor Super Game Boy fixes
26.95 Sept 2026
- Sega SG-1000 support
- Game Boy and Game Boy Color performance improvements
- Super Game Boy compatibility fixes
- Higher-quality LCD effects
- The launch window and game settings can override a game's cartridge board, console, and TV standard
26.81 Aug 2026
- Atari VCS (2600) support
- Save states and input recording with deterministic replay
- Game Boy Printer emulation, a persistent MBC3 real-time clock, and IPS/BPS softpatching
- Authentic display rendering: LCD pixel grid, CRT scanlines, and inter-frame blending
- The debugger now covers every system, with new memory, graphics, and per-channel audio panes
- Library search, sorting, and system filters, with a compact list view
- Performance and responsiveness improvements
26.74 Jul 2026
- Game Boy Color accuracy improvements