Face Stab

In the video game Team Fortress 2, the Spy class is able to instantly kill players from behind with his knife. But sadly, TF2's unreliable hit registration means the Spy sometimes instantly kills from the front.

Player 1: What the hell?! That was a total face stab! Thanks, Hitreg.

Spy: haha knife go poke

Trickstab

In the popular FPS Team Fortress 2, the class "Spy" uses his butterfly knife to instantly kill enemies from behind. This is called Backstabbing, and it usually involves sneaking behind players. However, Trickstabbing usually means the enemy is aware of your presence, and you still manage to strafe behind, jump over, or dodge them to still get a backstab.

Player 1: Stupid weeb, trickstabs are so unfair.

Player 2: Get over it, trickstabbing takes skill.