Into the Dead's [Free] latest update is a neat one, especially if you're looking to add some visual variety into the mix. Version 1.2 of the super physical endless runner sees the addition of football and WWII zombie "themes." Each cost 50K worth of in-game coins to activate from the main menu, and they can be swapped in and out anytime you want.
UPDATE: Initially, we thought this update also added Massacre Mode, a kill-based scoring mode with a "new" map layout. Apparently, it's been around for a bit (at least since December, but the patch notes aren't clear). Regardless, Massacre Mode is now a thing and it's pretty fun.
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