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Loving YTtalk
I don't know about full Christmas themed games, but a lot of multiplayer titles have Christmas and other seasonal events, giving the game that Christmas touch for a while. Team Fortress 2 has been doing that for years, and it's always a blast. WoW also has a good track record, and I heard rumors that Overwatch plans to do a Christmas event as well. So you could check out if any of your favorite mp games plans on doing a seasonal event..