Stampede: Racing Royale on Steam
store.steampowered.com
Welcome to the wildest kart racing event ever devised, where 60 players go bumper-to-bumper on outrageous circuits filled with power-ups. Avoid elimination and fight your way to the front of the herd in the scramble to be crowned champion!

Some friends and I stumbled across this last night and ended up spending hours playing it. Basically a MarioKart-style Battle Royale; 60 players, 2 20-player elimination rounds and one final round.

There are some minor UI bugs/improvements to be made, but the game is in free playtest until the 28th. Worth a peek!