This is a biiiiiiiiiiiiig old combo for thebronyshow.net 's art challenge. The previous two weeks' challenges were Derpy Hooves and More Derpy in honor of Derpy Day at the start of the month, and then this week's challenge was Ponies and Animal Crossing (and maybe Doom).
The whole "Doom Slayer loves tiny cute things" idea is adorable, so I just ran with it. Also fun fact, I thought this up before the Ponies and Animal Crossing (and Doom) challenge was even given. So I still count it as valid for that one. So there.