Although the introduction or power-boosting of Close Combat and Hi Jump Kick in recent years means Focus Punch is not of the same power level that it used to be, but it remains the most powerful fighting type move available, and with a substitute up, is far more reliable.
Ability: Poison Heal
EVs: 12 hp 252 atk 244 spd
-Seed Bomb/Stone Edge
While Techniloom is more common, Breloom makes a superb subpunch user, as it has a great base attack of 130, gains set up opportunities with Spore and can regenerate its substitutes in two turns with poison heal. It also has a good secondary movepool including Stone Edge, Seed Bomb and Facade. You may also run Leech Seed to make this a subseed set as well, but a more defensive spread is recommended.
Generic Substitute Attackers
There are some Pokemon that possess stats and a movepool to make any Pokemon jealous allowing them to severely injure most things in their path. The problem is however they are slow, have hindering weaknesses and/or do not deal with status well. Substitute remediates this and eases prediction
EVs: 4 hp 252 sp atk 252 spd
Hydreigon's healthy base 125 sp atk in conjunction with its diverse movepool allow it to be a very effective substitute attacker, and behind a substitute, one finds that its issues with speed and weaknesses to the common fighting and bug are manageable. Dragon Pulse provides STAB, while fire blast and focus blast provide good coverage. Roost provides recovery for creating further substitutes.