Defiler is good with a snowlion or gliding into the back of the enemy raid otherwise it has absolutely no mobility. In arena Defiler is very strong unless you get kited but if they make a mistake the CC chain is just too much for most classes to handle. If you want something similar ..Dreambreaker (WC/Aura/Def) is kinda close or just play Skullknight (Occ/Aura/Def).