Umbreon

Umbreon is one of the toughest walls to bring down thanks to its stellar defensive stats and access to Charm, which allows it to handle GSC's numerous Curse sweepers. It's also a solid Pursuit user despite being very weak offensively, since it doesn't fear much from Starmie and Dynamic Punch Gengar, unlike competing Dark-types Tyranitar and Houndoom. Umbreon can also make good use of the combination of Mean Look and Baton Pass, which is potentially very rewarding if the opponent fails to phaze it. However, with such poor offensive stats and its bare movepool, Umbreon is one of the most passive Pokemon in the tier and is left overly reliant on Toxic to do any sort of damage, which means it can't pose a threat to anything immune to poison except Gengar. Umbreon also despises status and has to use Rest in order to escape from poison and paralysis, and even though it is extremely sturdy, it can be overwhelmed much more easily when it is asleep.