Facing a swamp army with a calamity-class force like the gigantic hydra, even the sturdiest fortress was not really much stronger than an ordinary little village.
Red Tree Fortress had held out this long because it was garrisoned by four legendary powerhouses and one demigod.
The four legendary powerhouses aside, that demigod was a genuine strategic-level force. Even an army of thousands upon thousands stood no chance against him.
But the swamp army had demigod powerhouses as well.
For ages, the main reason the swamp races had been able to withstand human invasions was their demigod powerhouses, who lingered in the mortal world and refused to leave.
Some had become ancestral spirit totems for their tribes, some had produced countless descendants, and some cultivated themselves in seclusion all day long, never appearing before others.
But for the future of their races, at the summons and invitation of the Swamp Pantheon, and amid the pleas and calls of the swamp races, they had all stepped onto the battlefield.
At this moment, the swamp army surrounding Red Tree Fortress included two demigod powerhouses.
Two against one gave the swamp side a considerable advantage. Yet even so, they had no confidence they could keep that human demigod there.
Their opponent might not be able to defeat them, but he was at least capable of breaking out and escaping.
Or rather... if he refused to flee and insisted on fighting to the bitter end, the battle between them would likely engulf every living thing here, leaving them all dead without even a place to be buried.
Naturally, this was something neither side's demigod powerhouses wished to see.
Thus, the battle fell into a stalemate, becoming a prolonged siege.
But while Red Tree Fortress could hold out, the other fortresses could not.
By the time