Warning
This game is still beta quality and the project is still focusing on building basic functionalities, so expect bugs and many unfinished levels.
Note
This is the demo for Sonic Amateur Games Expo 2025.
Builds are provided in two formats: BIN+CUE (compressed as ZIP, ideal for burning on CDs or converting to other formats) and CHD (MAME Disc Format, recommended for emulators and portability).
Each format also has three different versions, one for each region of your console (Japan, USA, Europe).
There are no differences between regions, except that the European build runs at 50FPS.
Warning
While this game has been tested on a real SCPH-5501 model, there is no guarantee that this game will work on unsupported hardware or on alternate emulation methods, even if these methods are "official emulators".
For example, this game is known to crash at boot when running on a PSP, which contains an "authorized" emulator for the PS1.
This is because PSn00bSDK performs certain operations related to hardware and memory mapping that aim to "correct" the way it was normally done with the official PS1 SDK, and some old emulators simply do not support these operations at all, as some bad practices were simply "normalized", even at BIOS level.
Changelog
- Prevent situations where TOC wouldn't be loaded correctly
- Add Amy Rose! Amy jumps higher than the rest of the cast, has a lower top speed and slips down steep slopes more easily than the rest of the cast. She also has a Piko Piko Hammer Attack, a Piko Double Jump, and a Piko Spin Attack.
- Add framework for extra hitboxes on player
- Add Tails/Amy extra hitboxes (Piko Piko Hammer, Piko Spin, tail attack)
- Generalize behaviours on bosses and objects for ease of use
- [R0] Fix a bug where the boss would continue going forward when defeated out of a swing animation
- Add SPU SRAM debriefing on space available/used/free
- Add hearts when Amy hits the ground with Piko Piko Hammer
- Make Amy and Level Select unlockable upon beating campaign
- Add a special text slide feature to show special messages
- Render animals in front of player
- Make animals from end-of-level capsule jump around the player
- Show number of disc tracks on options menu instead of level select
- Add a secret code to unlock all unlockable features
- Fix a bug with player top sensors that allowed weird vertical zips
- Add spindash dust, slightly fix spindash animations
- Add default color function, escape sequence, and allow fade values for text
- Amy's Piko Piko Hammer can destroy bombs (R0) and enemy projectiles (R2, R3)
- Fix Tails's tails on Spindash animation
Known bugs
- Collision issues: random speed resets may occur on some wavy ramps, especially on the Test Level. This is because of how collision is resolved along linecasts, and will be solved at collision refactoring.
- Lack of 360° collision: The full 360 degree collision modes are currently deactivated on code because they still need work. Levels presented in this demo do not have big loops, so it is not really a concern for gameplay on main levels.
- Small memory leak when respawning level: For each item monitor respawned when the player dies, a memory leak of a single byte or two may occur since monitors use "extra properties" to determine their subtype. This will be fixed soon since object states now have a proper subtype slot, but this memory leak will be insignificant on most scenarios, and should only cause problems after an unrealistic number of respawns.
- Characters may appear slightly above ground on certain objects and platforms. This behaviour relates to how character rendering works and will be fixed once the new 360° collision feature is refactored.