gaccel is gravity acceleration, not key :3 sorry my comment moved somehow

if you want to make a coyote time feature change line 93 to this:

93. if (player.y > jumpbuffer + 2) then

Some ideas for beginners to implement:

1. Ensure the key and door are reachable, at least approximately so (like with simple distance constraint).

2. When player reaches door, increment score and generate a new level. Reset score on death.

3. Implement weird tiles like a bounce pad, an insta-kill platform for the player to avoid, a tile that prohibits the player from jumping, etc.

4. Start with more tiles. As player accumulates score, spawn fewer tiles or more random special tiles.

5. Every 3 or 5 points, the player earns a free level skip. This also gives the player an escape latch for impossible levels.

6. To give the game some lipstick, create noncollidable grass/background sprites to place in the tile above each collidable tile to make it look more like floating islands of land or something.

It doesn't take much to make a fun little time-burner game. It's mostly a matter of getting surprisingly small details to feel right.