low key mario is a phenomenal choice. He turns regular fauna and foods into magical powers to sustain life. Who else can touch a leaf and fly . Put on a tanookie suit you find in a box and turn to stone ...dude touches a feather, puts on a blanket and can fly indefinitely...
the only issue is, i doubt he will have success jumping on bullets in this scenario
I believe Mario would actually thrive as a side kick... especially in the Dead Space universe...
If this evil nikka took your family and he is 10 worlds away and one of those worlds are the "Dead Space Universe", that lil italian nikka is dog food by himself, he has nothing to chop away at their limbs and yoshi would turn necromorph while Mario was riding him(no hibbert)