Neat little project - I used Gdevelop in my early ears (NOSTALGIA HITS HARD). Under no circumstances should you assign jump button as a W key - most platform games have a dedicated jump button since the Super Mario Bros. "If it's working, don't fix it". Some technical feedback:
- Add some eye frames (if exist, extend the duration of eyeframes)
- Proximity mine's hitbox is strange, cause can detect collision out of space (near the stairs -that is a rat move)
- (maybe a Gdevelop's problem) - SFX played with a delay - ~ 1s
- Good thing to reuse assets, but change them a bit, if they have different actions (like different color of the sparks depending wheter their movement is horizontal or vertical, etc)
- add a "hold JUMP to JUMP higher" mechanic - then Player has more control over the character and it feels good + adds possibilites to YOU to build YOUR LEVELS differently (win/win/win)
Overall, good game - enjoyed playing, keep working )