Zombayz: What are you wiping your axe down with? The axe metal is pretty resilient stuff so the acid from the tentacle creatures isn't exactly eating through it... but it is smoking and leaving some pretty wicked etching in the blade.
Ears: I'll think about it

You want to do some investigating, investigator?
Mickle5125: I'm not prone to give you all... you know the answer but I'll just say this. You felt the creatures were reacting at about 1/4 of your speed

Madrigan: That should totally be it's technical name. Also:
[ Spoiler ]
The littlest viking looks close to tears if that's possible. His astral form shimmers and for a moment you're afraid he's going to actually disassociate. But he pulls himself together and begs your forgiveness as he recounts how he saw nothing! Nothing larger than a rat! He has no idea how he missed these things but he was sure that he looked hard enough.
Dumori: I have no idea what the anime test was for but the other tests yield the name and some info (it helps that you know now that it secretes acid, likes to drag people into the water, and seems to prefer ambush to frontal assault). At anyrate you ID the critter as:
Scyphozoa fidealis Common Name: Fideal
Executive Summary: The fideal is a freshwater creature normally found stalking reeds or other water grass around the edges of bodies of water. It normally grows to no more than 0.5 meters in diameter but larger specimens have been reported. Fideal typically hunt by waiting in obscuring flora and striking with their numerous tentacles at anything that swims by. In the case of larger creatures fideal will typically wait to be stepped upon before entangling the prey and dragging it under the water to drown. All the while the fideal will secrete an extremely reactive digestive enzyme that dissolves most substances aside from: Gold, stainless steel, and various other rare metals and alloys. The fideal feeds by macroscopic variation on phagocytosis, it completely engulfs it's prey in a phagosome and secretes special enzymes that rapidly dissolves it's prey. This process can take days and the various inclusions can often be seen within the fideal's gelatinous mass. Reports of undigested substances remaining for months or years inside a fideal inclusion are not unheard of.
Fideal is capable of altering it's body to have virtually the same refractive index as water and therefore is virtually impossible to detect using visible light. It's unique biochemistry also means it gives off very little heat. Their unique chemistry also makes them very suspectible to fire, their digestive enzymes burn readily as the heat denatures them.
There's more of course but the the rest is a technical discussion about genemapping efforts, some discussion about whether fideal is natural occurring or not, and some speculation on uses for it's very impressive digestive enzymes.
But some things jump out at you:
1. Fideal seems to be unusually adaptive. Saltwater variants have been reported and it's been known to alter it's behavior to better conceal itself in it's chosen environment. It's even been reported to move short distances on dry land, using it's jelly like body to squeeze through incredibly small cracks.
2. Fideal isn't this big. These fideal are some of the biggest ever recorded and that might account for some for their aggressiveness.
3. There's some mention of fideal being used to monitor local vermin levels by capturing them and counting their inclusions... still very hypothetical.
GM Freebie: There are at least two ways you can flip this combat for some cold hard cred, I'll leave it to you guys to figure out how.