Blocks

Metal Blocks

 * Blocks movement and projectiles.
 * An explosion's blast radius will not extend past it.
 * Cannot be destroyed or removed.
 * Can only be destroyed by walking over while is active.
 * Can be re-rolled by the into a destructible obstacle.
 * Can only be moved over via flying or jumping.

Key Blocks

 * Acts like Metal Blocks.
 * Requires a key to unlock.
 * Cannot be flown over.
 * Small chance to drop a random pickup when unlocked.
 * Can be destroyed without consuming a key by walking over while is active.
 * Can be destroyed without consuming a key by the effects of or.

Pillars

 * Blocks movement and projectiles like a regular block.
 * Cannot be flown over.
 * Can hide pickups, buttons, or enemies behind them.