: Certain powerful weapons, like early-game rocket launchers, are hidden behind "secret" doors that only unlock after specific interactions or reaching certain milestones.

: Saving credits found in early-game secrets is the most reliable way to afford the Ion Cannon , widely considered the best weapon in the game. Tips for 100% Secret Completion

Why look for these secrets? The difference between a standard run and a "high quality" completionist run is massive.

: Computer terminals or lockers that can be interacted with to unlock nearby stashes. Community Perspectives on Completion