I haven't seen this set on here, but it's more for a physical wall. It want's to setup, take an opponent down (maybe 2), then trade it's life to allow a revenge sweeper to come in.
Ability: Iron Fist / Guts
Nature: Impish (+Defense, -Sp. Attack)
Evs: 252 HP, 252 Defense, 4 Atk
Item: Leftovers
Bulk Up
Drain Punch
Ice Punch
Thunder Punch
Iron Fist lets him hurt right away, but leaves him susceptible to status and stalling, which is where the Guts comes in. However, with support from Aromatherapy or similar moves, Iron Fist brings a lot of upfront power and great neutral coverage. Guts without a status orb seems weird, but it's about mind tricking them into thinking this Conkeldurr has a different ability.
This Conkeldurr won't last long against special attacks, especially those that resist it's STAB, so this guy really wants to come in on a physical opponent, set-up and wipe. This is where trappers come in, with moves such as Whirlpool, Wrap, Infestation, Fire Spin, etc.. These moves can easily give you time to switch, Bulk-Up once or twice, then proceed to KO.