Infernape's Passion

Mixape @ (Life Orb)
Nature: Naive
EVs: 252/Spd, 128/Atk, 130/Sp.Atk
Ability: Blaze
Moveset:
~Close Combat/Focus Blast
~Flamethrower/Fire Blast/Flare Blitz
~Stone Edge
~Grass Knot
This set really gives a chance to wreak havoc on any team. With both the Atk and Sp.Atk being equal at 276 you can put a hurting on any team. Close Combat is probably the best choice for the first slot, because of the common Blissey, and it has better accuracy. Although Focus Blast does come in handy against pokemon like Miltank. Flamethrower is no doubt the best choice for the second slot. It has STAB like the others, but it has better accuracy then Fire Blast and no recoil damage. Fire Blast is stronger then Flamethrower, but the lose of accuracy hurts you a bit because Infernape can't take many hits. Flare Blitz is also stronger, but the recoil damge just doesn't help Infernape. Stone Edge helps to kill Dragon/Flying Pokemon such as Dragonite, and Salamence. Energy ball fills the final slot and helps Infernape kill many of it's counters, but the main one is Swampert.

Damage Calculations
Close Combat VS 252/Hp, 252/Def Bold Blissey does from 101%-117% of damge. A OHKO to any Blissey.
Focus Blast VS 252/Hp, 6/Sp.Def Impish Miltank does from 133%-157% of Damage. OHKO
Stone Edge VS 6/Hp, 0/Def Adamant Dragonite does form 70%-83% of damage. A 2HKO
Stone Edge VS 6/Hp, 0/Def Adamant Salamence after Intimidate does from 53%-61% of damge. 2HKO
Grass Knot VS 252/Hp, 252/Def Impish Swampert does from 68%-80% of Damage. 2HKO

EV Spread and Nature Choice
The nature choice is Naive so you can Even out both the Atk and the Sp.Atk, and be able to outrun most of infernape's counters. Speed should always be maxed out to outrun most counters. Then, even out the Atk and Sp.Atk by putting 128 EVs on both of them to make it an even 276 on both. The rest don't matter because you only have 2 EVs left whitch can't do anything for you.