How do you attack a tile or a target on the map for the first time?

On the map you send armies (a dragon leading, with its troops) at targets: territory tiles, beasts and wild dragons, Hedge Knights or Seats of Power.

In practice:

1. You pick your dragons first (up to 3 per army: Left Flank, Center, Right Flank), then the army's troop type.
2. You fill the troops to the max.
3. You send the army at the target. The fight resolves automatically, over up to 10 rounds.

Beginner's tip: damage carries over on a target. If a tile holds, send several waves in a row — the defender never heals, so you break it eventually (19,500 → 12,000 → 6,000 → 0).