Halcyon.
@Choice Specs
I really like Manibuzz right now. Like Alexander. said, it can check not only Latios, but also Landorus, taking pitiful damage from HP Ice and Focus Blast. The only problem with it is that you have to pair it with a spinner, since, with Stealth Rock, Landorus has about a 30% chance to 2HKO with Focus Blast. Same goes for Latios, who can 2HKO Manibuzz after Rocks with Specs Draco Meteor. Still a really cool Pokémon that not many people are prepared for. It has a small niche, but a niche nonetheless.