Board Thread:Questions and Answers/@comment-27327020-20160404174206/@comment-4995895-20160408002504

Actually the weakest charactor is Mettataon NEO. He has something like -40000 Defence and can't attack

And about Sans, yes without Karma it would be an easy fight. However, he still has some of the most difficult to doge attacks in the game plus he can just move away from attacks. And he has the glowing eye attack which I think the only reason it doesn't kill you is your determination