All castles in Heroes 3.

Why don't we talk about the Swamp faction more often? After all, the Swamp is the Swamp. We take the hero Alkin with his excellent specialization – Mighty Gorgons. We take the Basilisk with their ability to petrify enemies. We take the Serpent with their slowness, and finally, the Hydra with its ability to attack several units simultaneously. And I'm not even mentioning the Wyvern – magic exists, but they die like flies. And the magic isn't that strong, but there are other castles you can simply enter and learn from.