VS Threads with different tiers?

[Robot972]

What exactly are the rules regarding this?

While I've mainly only seen it with Human/Athletic and Street/Wall, you then get to profiles like Sans where they get to fight whoever (Which, yes, I'm aware is because of his hax.)

It's not really talked about in the rules. It just says to not make a spite/stomp match

 

[The_Wright_Way]

Don't make it a stomp match.

That's the only rule.

 

[ExSENNA]

Tiers don't matter as much with characters similar to Sans due to his Durability Negating attacks and dodging skills

 

[Robot972]

Got it.