The player has fully upgraded two weapons

The player has defeated Andrew Ryan

The player has purchased every slot in one of the Plasmid or Tonic tracks

The player has completed Sander Cohen's great masterpiece

The player has successfully completed 50 hacks

Collect 100 Light Seeds.

Block 50 attacks.

Use the Compass.

Talk to Elika.

Win a wall mini-game in combat.

The player has successfully invented at least one item

The player has defeated Peach Wilkins