
Aggron
Screw Aron. Aggron is where it's at.
Singles
Autotomize Sweeper
Nature: Adamant/Jolly
EVs: 252 Attack / 252 Speed / 4 HP
Ability: Rock Head / Sturdy
Item: Leftovers / Life Orb / Wide Lens
-Autotomize
-Head Smash / Stone Edge
-Aqua Tail / Earthquake
-Brick Break / Superpower / Fire Punch
After a Rock Polish, a max speed Adamant Aggron reaches 204 Speed, outspeeding all unboosted max+ 130s, +1 neutral base 83, and +1 +Speed 71. Meanwhile, Jolly Aggron reaches 224 speed, outspeeding anything unboosted in the GBU except Ninjask. If you opt for Rock Head, almost everything after Head Smash is filler - its sheer power is enough to KO most foes that aren't especially bulky, even when resisted. In fact, it can 2HKO max/max Impish Skarmory with a Life Orb. However, Sturdy's benefits can be hard to ignore. In that case, run Stone Edge, and pick your attacks more carefully.
SubPunch Aggron thanks to Tenodera
Nature: Adamant
EVs: 252 Atk / 252 HP / 4 Spe
Ability: Rock Head
Item: Leftovers
-Substitute
-Focus Punch
-Head Smash
-Aqua Tail
Pretty self-explanatory, don't you think?
Other Options: There are a few. Curse+Metal Burst, Hone Claws, and various other coverage moves. However, Hone Claws dies rather quickly, and moves such as Iron Head and Dragon Claw really don't compare to some stronger moves.
Doubles
Triples
Launcher
Rotation
Might add more later, but for now I'm only working on singles.