So I've been looking through BSTs and I'd like to point out an alternative to Breloom and Lucario: Hitmonlee.
Hitmonlee: +15 HP / +85 Attack / +18 Defense / +0 Special Attack / +75 Special Defense / +52 Speed
Ability: Limber, Unburden,
Reckless
Notable Moves: High Jump Kick, Fake Out,
Mach Punch, Rapid Spin, Stone Edge, Earthquake
Tyrogue's garbage stats translate to wicked boosts to its Atk/SpDef/Spd, and it contributes both Mach Punch and High Jump Kick at the cost of a secondary typing. But the kicker (heh) is that it contributes
Reckless on top of that. This can be pretty scary on a few Pokemon, such as:
Ponyta: 65 HP / 170 Attack / 73 Defense / 65 Special Attack / 140 Special Defense / 142 Speed (Has Flare Blitz/Wild Charge)
Cranidos: 82 HP / 210 Attack / 58 Defense / 30 Special Attack / 105 Special Defense / 110 Speed (Has Head Smash)
Rufflet: 85 HP / 168 Attack / 68 Defense / 37 Special Attack / 125 Special Defense / 112 Speed (Has Brave Bird)
Murkrow: 75 HP / 170 Attack / 60 Defense / 85 Special Attack / 117 Special Defense / 143 Speed (Has Brave Bird)
Doduo: 50 HP / 170 Attack / 63 Defense / 35 Special Attack / 110 Special Defense / 127 Speed (Has Brave Bird/Double Edge)
Ponyta: 70 HP / 170 Attack / 73 Defense / 50 Special Attack / 130 Special Defense / 112 Speed (Has Flare Blitz/Wild Charge)
While many of these Pokemon lack access to Swords Dance (just Cranidos), STAB Reckless attacks backed by HJK coverage makes them fearsome wallbreakers from the get-go. While not top tier I think it warrants mention as a specialized option.
EDIT: One more I forgot to mention...
Meinfoo: 60 HP / 170 Attack / 68 Defense / 55 Special Attack / 125 Special Defense / 117 Speed
Say hello to Mienshao 2.0. (Mienshao itself also provides Reckless HJK and
does offer Swords Dance and U-turn, but it gives a lot less Attack, less Speed and loses Mach Punch and a few utilities.)