Aegiaslash should be good with prankster, and possibly regenerator(abuse u-turn and status), possibly abuse protean plus priority to play prediction games.
magic guard/bounce could feasibly be abused.
Levitate/Flash fire could add some useful imunities
if it weren't steel toxic heal would be a nice option.
Loosing out on king's shield is unfortunate but access to better status options and defensive abilities should make up for it
Snaquaza you should add any unbans to the OP
edit:
Aegislash @ Leftovers
Ability: Prankster
EVs: 252 HP / 4 Def / 252 SpD
Careful Nature
- Will-O-Wisp
- Recover/pain split
- Magic Coat/taunt/substitute/protect
- Knock Off/calm mind
wow to decrease physical damage and the majority of damage out put would come from here
recover is of course for recovery
Pain split nice on something with this low of hp but slightly inconsistent
magic Coat/taunt are for hazard control and status prevention
sub helps prevents status as well and can allow to take advantage of switches to the best ability
protect is to boost passive recovery
calm mind works in counter point to wow to boost special defense
knock of is for generic utility