I'm gonna give you both dusknoir and eviolite dusclops movesets:
Dusknoir:
Dusknoir@Weakness Policy
Ability: Pressure
EVs: 4 HP, 36 ATK, 252 DEF, 216 SPD
Nature: Impish (+ def - spa)
Moves:
Will-O-Wisp (burns the foe, with all this defenses and the attack drop it will be hard to kill you with physical attacks)
Shadow Punch (STAB, always hits, after the weakness policy it will be dealing a good damage even with the low power)
Destiny Bond (is hard to kill you, so you will most likely hung on with a low HP anyways. then you destiny bond and bring your opponent down too)
Trick Room (destiny bond won't do anything if used by a slow Pokemon without trick room, plus you will be able to hit them first. use it)
Dusclops:
Dusclops@Eviolite
Ability: Pressure
EVs: 4HP, 252 DEF, 252 SPD
Nature: Impish
Moves:
Will-O-Wisp (burns the foe, as I said before, but dusclops is even bulkier, so... yeah)
Destiny Bond (dusclops is even bulkier than dusknoir, it should be able to work even without trick room, for attack last)
Counter (for if they hit you too hard)
Seismic Toss (level 100 dusclops will always deal a great amount of damge to the foes, it just even 8HKO Blissey max HP. but against it, you can deal super effective counter. but seismic toss is always a good moveset moveset for eviolite Pokemon; use it)
