Collect all memory cubes
Help Big Guy
Defeat the last claw
Power every gear nest at least once
Collect half the memory cubes
San falls inside the factory
Help Big Momma
Throw your spear and retrieve it 3 times without it touching any surface
Finish the game
Escape from the factory
Throw a spear against a Beetle
Collect the first memory cube
Complete every achievement
Help Old Guy
Boulder falls on your head
Recall a spear for the first time