The ugly looking human calling itself Freakshow laid out a plan that Mire thought was at least reasonable. Some of them going in, others staying out as bait. It made sense, even if she talked too much. Mire would've actually gone through with it, had the gunshot not happened. They knew what those loud noises meant, humanity used them to scare things off and kill to eat. That much was clear, so it stood to reason that the sniper had shot one of the Terrazards. At that point, things stopped being so complicated. People starting rushing in, the ground started splitting wide open. The fungal monster was smart enough that they could make their own plan at this point.
"Now they know we're here. That plan means nothing at this point. I'm going in, and I'm making them all do the hard work for us," Mire said, to the remaining heroes who hadn't sprung into action yet. They flicked their arms out, and small particulates of spores drifted downwind. "Don't follow me."
And then they calmly started walking forward, trudging across concrete and metal wire fences while the others did their work. Mire's body pulsed and contorted, like something was writhing under the surface of all that mycelium. Bulbous growths start poking through like septic boils, which sprouted new fungus that sloughed off to the ground. It took root, and Mire just kept marching forward towards the hole that the Terrazards were coming through.
"YOU EAT HUMANS, DON'T YOU?! COME AND TAKE A BITE FROM ME, THEN!" Mire's awful voice boomed across the ruins of the plant, alerting swathes of Terrazards to their exact location. It might've been stupid, but that was what they wanted to happen. Their hypae structures stretched out, making Mire seem taller than they actually were as their limbs grew more and more gaunt by the second. The eyes of Terrazards nearby turned and glared at the strange, vaguely humanoid looking entity just beckoning to be eaten alive. They were intelligent, but many of them saw this and took it to be a sign of absolutely stupidity. And so, an entire herd of the beasts descended on their fellow Leftover. Like a swarm of starving piranhas they bit, chewed, clawed and tore into what they thought would be a warm and bloody snack. But instead, their teeth bit down into saturated sludge. Mire didn't fight back, they wanted the creatures to get as much of a mouthful as possible, so chunk after chunk of their body fell away in a feeding frenzy.
And then, the flood came.
Every Terrazard that bit into a piece of Mire had its mouth, throat and stomach filled with enzymes as Mire's body exploded. It was like a giant water balloon, splashing everything around the living colony. In an instant, the feast became a mass grave as the Terrazards melted like warm wax, right before the eyes of everyone who thought to observe. They howled and writhed in agony, but their bones and their flesh leaked to the ground. Limbs decayed in seconds, bones and blood mingled into a slurry. And in the runoff, there sat Mire. Tattered and practically swimming through a puddle of half-decomposed gore. Even the ground they stood on was slowly dissolving.
A few were still alive, but their bodies were in such bad shape that it was just cruel not to kill them. Mire sloshed through the pit of rotting guts and enzymes, subsuming the survivors into what parts of their body still squirmed. The Terrazards didn't even fight back.
As effective as it was, the move Mire made was filling the area with a ghastly stench.
"That was easy."