The best multiplayer games usually keep the player glued to the game and keep it hard to get away from. 2014 saw a lot of that especially with the addition of next-gen consoles really starting to show their muscle.
Super Smash Bros. For Wii U
While most multiplayer games this year were more of what we have already seen, Smash Bros. brings back the joy of playing games with your friends as a kid. Seeing your favorite Nintendo character that you remember as a kid or grown up routing for is something that no other game and beat. Smash Bros. has always been one of the most competitive games ever created and the addition of smooth online play just made it that much better.
Runner-Ups
World of Warcraft: Warlords of Draenor
———————————————————————————————————————————————————————————————————————————————————————————————
Mario Kart 8
———————————————————————————————————————————————————————————————————————————————————————————————
Call of Duty: Advanced Warfare
———————————————————————————————————————————————————————————————————————————————————————————————
Destiny
———————————————————————————————————————————————————————————————————————————————————————————————
I'm in North America, I'm just not super familiar with the series.