lol i found this to be really funny ok get out a level 2/3 dragon sword/plasma saber and do XY against any chp 6/7 zombie. it should flinch back. after that do ->YXXXX for blade of nirrti. you should not kill it. do fiend sealer against it and it should die. works on very hard too!

after you kill two don't take the essence. get out your vigoorian flail and do gathering clouds. the last two hits can kill a zombie even on very hard! (you can kill 3 zombies back to back easily with this, and if you are lucky, you can do the 100 fiend challenge without dying!)

issue is that if these zombies are attacking before you do anything you must wind path over their heads before doing this.