"I dont know but kill it while its asleep. it will wake up soon. attack all at once"  she walks up to the creature "come on guys on three" 

(due to it being unconscious if you are within 5 feet of it you get advantage to hit and melee hits are crits. but its only asleep for 1 minute)

The creature snores peacefully and quietly... 

Amthrum is up with Saein.on deck, unless youd like to do some sort of coordinated finisher or something

Quote from ChrisTheSoulcasterMage >>

The creature snores peacefully and quietly... 

Amthrum is up with Saein.on deck, unless youd like to do some sort of coordinated finisher or something

 (yeah...that would be fun)

"everyone, get a sharp weapon. on my count, plunge it through this things skull while screaming. yeah?"

Arb makes no move to join the final blow, but does watch as it happens

"aim for it's head, I need it's heart intact" she rasps

"everyone ready then"

(ready actions are our friend right now take the ready action so we can all attack at once)

"I've had enough of those fangs!" and Sayax drops his shield and readies his attack for his warhammer to bust the creature's jaw

Attack: 16 Damage: 7

(Sorry forgot about it being asleep)

Attack: 21 Damage: 24

Arb readies an action to closely observe the creature in its moment of death, specifically how the already perceived corruption possibly changes during the change of state, she will get as close to it as is necessary for the check.

15 attack 1 to hit

20 attack 2 to hit

12 attack 1 damage

20 attack 2 damage

25 total damage assuming both hit

(Sorry forgot about it being asleep, so if you'll allow this... if you don't I understand)

Attack: 26 Damage: 16

(I’m guessing that did it but if not, Saein will throw a firebolt in for good measure)

19 to hit

13 damage-  some DMs use auto crit for unconscious creatures not actually sure what the rules are.

(i'm following rules as written rn. if i am told otherwise then i will follow that but as written it says this

• An unconscious creature is incapacitated (see the condition), can't move or speak, and is unaware of its surroundings
• The creature drops whatever it's holding and falls prone.
• The creature automatically fails Strength and Dexterity saving throws.
• Attack rolls against the creature have advantage.
• Any attack that hits the creature is a critical hit if the attacker is within 5 feet of the creature.)

Its jaw snaps in half, as it lets out a final waking yelp of pain, before going still and limp. Arb, perception please.

(Thanks for the unconscious rules refresher!) 

Perception 19 

Arb leans in muttering under her breath as the beast takes its final one.

Quote from YorkshireJoker >>

Perception 14 

Arb leans in muttering under her breath as the beast takes its final one.

 The corruption seems to fade.... Dying as the beast does

Sayax comes over to Arb and looks where she is looking, "What are you trying to see?  It's dead, we bested it!"  He turns to the rest of the group, "Great job team!"

What does the corruption look like? Now that she can see the dead form of the now uncorrupted beast.

Quote from YorkshireJoker >>

What does it look like?

 Its.... A sort of dissipating cloud around it, almost. 

The beasts legs also shrink from long and spindly, to more shovel like. Sorta similar to a sea turtle

"a job well done maybe, but this is wrong something unnatural corrupted its form, something bad, yes?... Saein! I may need assistance" At this Arb takes the knife that was loaned to her by Mizu and attempts to remove this animals heart as intact as possible.