NHF – new heroes for Heroes V 3.1.

Are these pirates from NCF?

Added 36 minutes later
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Knight (no name yet) specialization description: When the hero captures a building for recruiting creatures of a different faction, it transforms into a Haven building of the same level. This will require spending some resources. Also, if an enemy hero tries to capture a building, they will engage in combat with the guards, whose number depends on the hero's level. But if they win, the building will return to its original state without the resources being returned.;)