Image Layers
    bg 1-5: parallax background layers 
Tile Layers
    decorations
    platforms
Object Layers
    blocks - bonkable, breakable (punch, crush, projectile), pushable,carryable, deadly (spikes, lava, etc)
    collectibles - coins, hearts, parachute, presents, treasure chest?, drinks, food, extra life
    enemies
    collision - level ends, edges, checkpoints