The most powerful warrior.

Of all the creatures at level 3, the most powerful warrior is the Elven Forest Archer. He has high initiative, which allows him to move before the opponent's archers, and no other level 3 creature deals as much damage as the Forest Archer!

Yes! He deals a lot of damage for a level 3 unit. He has the highest attack, but his defense is very weak, so he isn't the most powerful. After all, a creature's power lies in everything combined (attack, defense, hit points, immunity to certain spells). Even unskilled units like Knights or Demons can easily kill these "snipers" with Chaos magic.
The Swordsman, Minotaur, and Bear Rider are significantly more powerful, especially the last one. And the Swordsman is also almost immune to arrows.