Teutons are the most funky tribe in Travian and most successful raiders. They are very aggressive and their infantry are best in the game for their purpose. Clubswinger is very cheap and they are most important unit of Teutons
Unfortunately cavalry isn't best side of Teutons.
Teuton Hero allows raiding parties accompanied by him to loot resources off crannies, acting as if their capacity were 20% lower than usual (a cranny with a 1000 resources limit would only hide up to 800 when attacked by Teuton Hero).
This plunder bonus can be increased by having either the Pouch, Bag or Sack of the Thief equipped.
Clubswingers or Macemans however are raiding unit with medium attack but like I said they are very cheap and they are really useful in early stages of the game. Their defence is really bad but its aggressive unit so keep them away from battle when somebody attacks especially when cavalry is attacking.
Some players prefer them to be best in offense per cost per time per upkeep and per attack value.