I've been experimenting with Shelgon/Kecleon as my defenses. Shelgon has a wealth of resistances and has access to recovery via wish. Can tank those powerful hits from Rampardos and the like. Kecleon's Special Defense is insane and I think that people really underestimate his ability. Choice specs/scarf users like the 3 monkeys or rotom are forced to switch out since their hits suddenly become ineffective. He also has recovery and access to stealth rock. I like to run Knock Off on him because eviolite users are so common. Though the duo has an obvious weakness to dragons, since once Kecleon is hit by a dragon move they suddenly because super effective.