Zanz isn't an AU more like an alternate version of GazeTale!Sans, Zanz is actually meant to be similar to the alternate version of Sonic, Zonic, which is why Zanz is named Zanz. The story of how he came to be was that Zanz was just popped into existence he wonders around GazeTale hidden and hiding from the original version of himself.
Zanz likes to be isolated and alone alot, he also loves the taste of meatloaf and has a hard time around animals.He's up tight and doesn't like jokes as much as a regular sans would. He hates being in large crowds and has a beef with his other self that even he doesn't know why.
Zanz appears to have a white furry hood along with a white sweater. and wears black pants and has a nice pair of shoes. He also appears to have a shattered eye along with a huge scar the right side of his face.
this attack causes the entire battle field to turn to into a bombing field, for giant drips of blue and orange water coming pouring down upon you.
instead of using gaster blasters to shoot,Zanz instead uses them to charge at you with their horns facing towards you