Items

You'll come across various items, either in Chests, which often you'll need to solve a Puzzle to be able to acquire.

Amulets

 * Universe Tuning Amulet

Hacking Weapons

 * Magic Sword
 * Boomerang
 * Magic Loupe
 * Breakpoint Bombs

More

 * Third Eye Hat
 * Halcyon's Lamp
 * Ida's Device
 * Password Note
 * Artifacts

Interacting

 * GateDoor
 * HackBlock
 * Bush
 * PortRock
 * TurtleSpawner
 * Code Sign