Board Thread:Wiki Discussion/@comment-26843781-20160301110343/@comment-26343489-20160305142203

CrusaderDeleters wrote: Then take a picture of Gaster, Tofu. If you're sure, then I have reason to believe you've seen him before with your own eyes. I don't have the game.

But if your Fun value happens to get to 66 randomly, theres a 0.1% chance of a gray door appearing somewhere. That's where he is.