Cartoon Platformer Prototype Build

I want to see a small, cartoon-style 2D platformer up and running. The goal for this first milestone is a lean, playable prototype that proves one key idea: the player character can travel seamlessly through different terrain areas within a single level (think grassland into cave into mountain).

Scope for this initial build:
• Core movement, jumping, and collision that feel responsive.
• At least one short level stitched together from two or more visually distinct terrain zones.
• Simple placeholder art in a bright, cartoonish look—enough to show how the style will read on screen.
• A lightweight menu or restart option so I can loop the demo easily.

You’re free to use the engine you’re fastest with (Unity, Godot, or similar) as long as I receive both the playable build and the project files. Clean, commented code is a plus because I’ll expand on this later.

Keep it tight and focused—no power-ups, boss fights, or extra polish yet. I mainly need proof that the terrain-to-terrain transition works smoothly and looks fun in a cartoon setting.