Saw this creative simultaneous isekai where mc1 has the 10 shadows in JJK and does the reversal technique on it with the idea that "it diffuses user's shadow into 10, so reversal means fusion of different powers", and then this lets mc2-99 use other world powers, mc3 was in HxH and has a nen arena where he can loot enemies' powers, with nen as a medium, so mc4 can unlimited devil fruits
