merchbeast 

Someone who is incredibly skilled at selling merchandise in a retail store.

TTL Cuteness is a straight-up merchbeast at Forever 21. I wouldn't ever wanna compete for employee of the month with that guy.

merchbeast by ticktockterror November 30, 2009

mercbeast 

Someone who is incredibly skilled at a first person shooter.

TTL Cuteness is a straight-up mercbeast in Call of Duty. I wouldn't ever wanna run into that guy.

mercbeast by sundayisover September 18, 2009