Spiritomb - Kinda annoying due to having no weaknesses, but I managed to take it down with a couple of Earthquakes from my Garchomp.
Gastrodon - Giga Drain = No more Gastrodon, extremely easy
Lucario - Relatively easy with Infernape's Flamethrower/Close Combat
Garchomp - Mantine's Ice Beam took it down easily
Roserade - Flamethrower, next.
But one, just one pokemon was more anooying than anything. Milotic. I hated that thing, it kept on getting crits and knocked out my Roserade before I could even land a hit. I finally took it out with, ironically, the fire-type Infernape. (Close combat ftw).