I'd like to talk about some sets I used on the ladder today that really impressed me.
1) Galvanize Drill
Excadrill @ Leftovers
Ability: Galvanize
EVs: 252 Atk / 4 SpD / 252 Spe
Jolly Nature
- Swords Dance
- Rapid Spin
- Earthquake
- Facade
Works nicely as a Corviknight/Mandibuzz lure (for non VA variants), not to mention Ghosts can't spinblock it. Of course ground types can, but most ppl dont think to go into Ground types on an expected spin. Refridgerate would prob be a possibility too, but that doesnt punish corvi as hard. I'm not sure that running a second normal is even necessary or that facade is the right move (CrushClaw is another option with a nice 50% chance to get a def drop, just running Iron Head might be better too). Anyway it's really nice for punishing corviknight/ghosts that try to spinblock you, especially since the spin speed boost can let drill snowball out of control.
2) Psea Inteleon
Inteleon @ Choice Scarf
Ability: Primordial Sea
EVs: 252 SpA / 4 SpD / 252 Spe
Timid Nature
- Weather Ball
- Ice Beam
- Scald/Hydro Pump
- U-turn
I've been using a scarf set myself, and it's really impressed me. It's speed tier is already very nice but scarf lets it outpace a lot of stuff even at +1 which helps with revenge killing and it actually seems to ohko any offensive mon that doesn't resist water with the PSea boost. Weather ball is a really nice spammable accurate 100 BP stab, way better than hydro pump imo. It also has some utility in hitting desoland switchins for some nice chip instead of being completely negated. A specs set could probably work well as a wallbreaker, although you lose utility vs offense.
3) Unaware Corvi
Corviknight @ Leftovers
Ability: Unaware
EVs: 252 HP / 76 Def / 180 SpD
Careful Nature
- Bulk Up
- Body Press
- Roost
- Iron Head
This thing is a nice blanket check to a lot of setup mons (most importantly Pheal Lax and opposing BU Corviknight) and can even muscle past most physical Fire/Elec types after enough Bulk Up boosts.
Other than that, I'd like to echo what Thinkerino said about Drapion - its a really nice check for Gengar and special Pult, as well as most other psychics and ghosts. Can help vs Toxtricity as well as it likely lives any one hit and OHKOs back w EQ.