The player has completed the game on the Hard difficulty setting

The player has defeated Atlas

Successfully invent at least 100 items

Max out all possible research

The player has become a Big Daddy

Purchased every slot in all four Plasmid and Tonic tracks

Acquire all upgrades for all weapons

Fully upgrade five weapons

Fully research the Nitro Splicer

The player has entered Sander Cohen's personal quarters

Collect or Invent 58 Tonics in the Physical, Engineering and Combat tracks

Fully research the Little Sister

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