Every weapon in "Gears of War 3" has a unique execution animation
which plays if you hold down Y when approaching a downed enemy. In
campaign, all of these executions are available, but in Versus you have
to unlock them by getting a certain number of kills with that specific
weapon.
LANCER RIFLE
200 Kills
HAMMERBURST
200 Kills
RETRO LANCER
200 Kills
GNASHER SHOTGUN
200 Kills
SAWED-OFF SHOTGUN
200 Kills
GORGON PISTOL
40 Kills
BOLTOK PISTOL
40 Kills
BOOMSHOT
40 Kills
DIGGER
40 Kills
HAMMER OF DAWN
40 Kills
MULCHER
40 Kills
MORTAR
40 Kills
ONESHOT
40 Kills
SCORCHER
40 Kills
TORQUE BOW
40 Kills
LONGSHOT
40 Kills
CLEAVER
40 Kills