Defeat a squeaky foe.
Drain all of the water in the Aqueducts.
It will live on in our memory.
Fix the malfunctioning Heater Core.
Clean up the Ventilation System.
Finish the game.
Obtain the Repeater from Rebba.
Obtain the Hopper from Rebba.
Finish the game with 100% completion rate.
Finish the Heater Core before acquiring the Spin Jump.
Finish the game without collecting a single health upgrade.
Finish the game in under 1 hour.