>>533373445
You mean in general or in the pioneering thing?
Even in general, stat difference is what determines damage taken. Unfortunately stats matter a LOT in the game, so stat buffs/debuffs are also really strong.
In the pioneer thing level difference changes the mutation of the fight. Depending on your team and what you've unlocked you should be able to take a 7-8lv diff, even if your guys are getting oneshot.