Kommo-o typically runs two different sets right now enabled by its new tutor moves.
Kommo-o @ Dragonium Z
Ability: Soundproof
EVs: 252 Atk / 4 SpD / 252 Spe
Jolly Nature
- Dragon Dance
- Outrage
- Close Combat
- Earthquake
This is probably the more common of the two, Dragon Dance which became good when Kommo-o received a better fighting STAB than Sky Uppercut in Close Combat, allowing it a strong hit vs Steels like Durant and Escavelier, and a strong way to hit a lot of stuff for neutral damage in general without having to lock into Outrage. Basically, getting a strong STAB move without the massive drawbacks of outrage allowed DD to become much more effective, utilizing Kommo-o's natural bulk and power.
Kommo-o @ Draco Plate
Ability: Soundproof
EVs: 4 Def / 252 SpA / 252 Spe
Timid Nature
IVs: 0 Atk
- Taunt
- Stealth Rock
- Clanging Scales
- Flamethrower
This is the other set that's occasionally seen, which utilizes the addition of Stealth Rock to its movepool. This makes a pretty good rocker on balance and bulkier offenisve builds, as its able to both set up rocks, deny other common rockers like Nidoqueen and Registeel, and still often fire off a couple attacks with good damage output.