This Probably Sounds Really Dumb From The Outside Perspective - Tumblr Posts

What if Sans' invincibility frames were inspired by a hiccup during development?

Think about it: Toby programs damage into the game but forgets to add I-frames resulting in ludicrous damage during playtesting. While I have never programmed a game, invincibility frames are something the casual player never thinks about, so it seems like an easy mechanic to forget to add.

So Toby Fox realises he needs to add invincibility frames to his game and does so. But when it came to making the Sans fight, a fight against an character who you'd never expect to be strong but breaks all the rules, he remembered how the lack of I-frames made the even the easiest enemies do stupid damage and removed them again for this fight.

Now I don't believe this (I have no proof), but it's interesting to think about.