Use Pincer. It's the smite-damage formation, and both commanders deal smite damage.
Inscriptions to chase:
- Scroll: Dominate, Toppler. Then Bludgeon, Imploder, Ward, Robust.
- Instrument: Cleaver, Demolisher. Then Charge.
- Flag: Bulwark, then Airtight.
- Emblem: Tidebreaker, Thundering. Then Vigor, Rattling.
Dominate, Cleaver, Bulwark and Tidebreaker are the newer legendary Pincer inscriptions and the best you can get. Toppler, Demolisher, Airtight and Thundering are the older specials, still strong.
For a city garrison, swap the damage scroll for defensive inscriptions.