I was wondering if a bone was cut would it bleed? It does make blood cells and I am asking this because of a game called 'Undertale.'. In this one scene when you defeat the skeleton called 'Sans' he will bleed. I thought that maybe it could be proven by science that its blood and not ketchup. (See the game yourself if you want to know more about what I am talking about.) I don't think that it would just happen because of a link between games. (This was explained in Game Theory's video.) So could a bone actually bleed?

Yes human bones when cut or broken do indeed lose red blood cells and marrow.