Killgasm 

Getting "over-excited" after a large killing spree or an epic multi-kill.

"Reaver got a killgasm for getting three consecutive kills."

"Jones experienced a large killgasm for his monster kill in Unreal Tournament 2004."

Killgasm by Chapst1ck April 5, 2007

Killgasm 

Getting a kill streak of 20 in any online first person shooter match that causes a sensation to surge the body and make you dominate even more.

"Dude that was fucking awesome I just got a killgasm."

Killgasm by MIDKNIGHT22 January 21, 2009