Clear a Challenge in Challenge Mode.

Kill 20 enemies with Mk-NDI grenades

Kill five enemies in a row with a single punch, after softening them up with gunfire

Kill 30 enemies with the M79

Kill five enemies with a single punch, after softening them up with gunfire

Kill 100 enemies with headshots

Find the Strange Relic

Kill 20 enemies by shooting from the hip (without aiming with the L1 button)

Kill five enemies in a row with a brutal combo

Kill 10 enemies by aiming while hanging from a ledge

Release all of the names to the sky.

Completely awaken the city.

Light a darkened pool.