It seems to me that if you compare the Fortress soldiers individually with units of other factions at the same levels (1-1, 2-2...), then, perhaps, the Swamp faction won't look that impressive. But when they work together, they are a force to be reckoned with. Firstly, they don't have any useless units. That is, creatures whose development is not necessarily required (at least not in long games and not on TOO rich maps). For example, these are Cyclops in the Stronghold (due to their high cost), Knights in the Castle (they are generally needed, but buying them all doesn't make sense), Demons in Inferno (similar to the Knights), Gargoyles in the Tower (they become irrelevant as you gain experience and build Nagas and Titans). Perhaps someone will disagree with me (but this is my opinion). The Talia's army is interconnected and, when fully assembled, represents a formidable force.
The units in the Swamp faction are not bad, but some of them have very different levels of usefulness. For example, without ambushes and other tactics, the Lizardmen quickly become ineffective, and Goblins are not always used in the third week, although this does happen...
Overall, the Swamp faction is very strong, but I would attribute this to the presence of Tazar, Bron with their corresponding starting army, Snakes with their speed, upgraded Gorgons with their drowning ability, Hydras, and the quick construction of Wyverns.

Орден Феникса – харизматический :) лидер