What is your favorite Multiplayer game that you come back to play a few rounds and frag charlies on?

Pretty plebby but i used to play a lot of halo reach. Had a few good friends i'd play with, either custom games or big team battle but it was always a blast. One particular friend and i were a crazy good duo in a warthog, he'd drive i'd shoot. Got bad enough the enemy team would scatter if they heard us coming. And they would since we'd be blaring Los Dos Laredos Acordeones through our headsets while laughing and singing along to the tune like a pair of loud, obnoxious, maniacs. Good times.