act 3 is not going to end, stop buying the 5 acts fake news crowd t. if it had 5 acts, act 3 would end before they got to onigashima. right now it's very little left of this arc to end act 3/5. we are already at the final battle.
and if you really buy the 5 acts you should know that the battles only happen in act 4, not 3 so you already lost