Heads up, if you're still in the Whamageddon game, you might be entering into a grey area here. Some inspired YouTubers have created a mashup of "Last Christmas" and Slayer's "Angel of Death". You get the music from the ubiquitous holiday hit along with Tom Araya shouting the lyrics to the 1986 Reign in Blood album opener. If you stick around until the end of the track, you'll definitely be out of the game, with the Wham! song's refrain closing the piece. Slayer performed the non-mashed up version of "Angel of Death" to close out their final show last month.