The Chimera Ant Arc feels like the complete shonen horror package to me. The Chimera Ants are uniquely terrifying creatures whose evolution from simple ants to tactical powerhouses we get to witness throughout the 61-episode arc. The horror is spiced just right. Not too much of it, not too little. This arc is one of the finest foreign species invasions in pop culture. Thanks to how well they balance the players and just how powerful antagonists like Neferpitou and Meruem prove to be.