To kill "The End" I used Orcs, always try to keep 2 angels on him and just spam hobbits. (Keep pressing 1), He will die eventually as he cant get close because of the blockade of hobbits.
Level 103, then got bored so suicided lol, was ok besides the lagg after level 90+, no next wave key and floors dont work against flying monsters. 3/5.