Accomplish the indicated achievement to get the corresponding number of Gamerscore points:

Hard To Crack (10 points): Finish first in a round of Battle Royale with the shield still intact.
Too Cool For School (10 points): Give Ralph a big owie.
King Of Comedy (10 points): Respawn into a missile and die.
Brawny (10 points): Finish first in a complete Multiplayer match of at least 3 rounds of Battle Royale.
Geddowned! (10 points): Use a Wormhole Disrupt to block a foe's Monster Attack within a second of it launching at you.
Wait For It (10 points): Use a Missile Boost on an attack less than one second before it's hit by an Anti-Missile.
Try Anything Twice (10 points): Reflect the same missile twice.
Duelist (20 points): Defeat a total of 100 foes in Multiplayer.
Meet Your Maker (20 points): Defeat a total of 50 Hard Bots when playing as the Robot Factory.
Even-Steven (20 points): Defeat a total of 50 opponents after you have been killed.
Rest In Pieces (20 points): Accumulate 150 Dead Puzzler's points ten times, in Multiplayer Battle Royales.
Puritan (50 points): Clear the final level of Poison Peril.