You have to get 100% or you won’t get your reward. At least if the reward is a monster.
Yeah, crap just found that out before checking back here again. Just got 97% and it is for gear. So safe to say you have to be at 100%. So close.
You need to destroy everything inside dungeons i. e. - you have to get 100% to proceed further.
If you got 97% keep it up, you’re almost there .
1 Spell or Unit Upgrade should also do the trick