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As I understand it, due to the high defense of the Swamp units combined with the high defensive stats of Swamp heroes (e.g., Tazar), capturing the Serpent Hive is relatively easy, or rather, without significant losses. Furthermore, the free Wyverns obtained there don't lower army morale and can be upgraded in their native Castle.

Орден Феникса – харизматический :) лидер