Monferno @ Choice Band 
/ Fist Plate / Firium Z* / Life Orb / Eviolite
Ability: Iron Fist
EVs: 252 Atk / 4 Def / 252 Spe
Jolly Nature
- Close Combat
- Flare Blitz
- Mach Punch
- U-turn / Swords Dance*
Monferno is a fearsome attacker in the ZU metagame, having excellent offensive coverage with its STAB, a priority attack boosted by both STAB and an ability, and U-Turn. On its own it's an incredibly dangerous threat, but faces problems from a few Pokemon that can take on its combination of STAB and survive for later, most notably Grumpig.

Liepard @ Black Glasses 
/ Choice Band
Ability: Limber
EVs: 252 Atk / 4 Def / 252 Spe
Jolly Nature
- Knock Off
- Pursuit
- Sucker Punch
- U-turn
Liepard backs Monferno up in its efforts of picking apart opposing teams, removing problematic Pokemon through its highly versatile STAB options. Knock Off removes Eviolite and Leftovers to make Monferno's job easier, Pursuit traps problematic Pokemon that resist one or both of Monferno's STAB and Sucker Punch finishes off weakened Pokemon or weakens them.
---Teambuilding Weaknesses---
Together this duo can pivot to each other to handle problematic Pokemon for the other and pick apart some teams entirely. However, this duo do have weaknesses that must be considered. The two may pair well offensively, but defensively their low base bulk stats leave much to be desired. The two together can also be threatened by a sturdy physical wall that is not weak to any of their STAB, most notably Poliwrath, which means a partner that brings an offensive presence as a special attacker is highly appreciated. The two also greatly appreciate hazard support and hazard removal because of all of the switching they force and pivoting they have to do. This core also fears fast attackers that cannot be easily threatened through priority, although it's worth noting that a Choice Scarf Monferno set could also function for this core.
(* = Use Together)