Alright so this guy is a yonko in a one piece campaign so needs to be hardest fight.
Idea is for it to be a 3 stage fight where each time they drop his hp by 400 avg he runs away letting them short rest (he won't).
Is the gimmick idea itself good?. He will only make 2 attacks each round and as legendary action can recreate any 8th level spell twice per encounter.