A macabre scene unfolds itself at the edge of your torchlight...as the 2 grey oozes meld into one blob pushing itself grossly through the secret portal.
Those choosing to shoot range weapons manage to get off 2 volleys (with a bonus to hit).
Attack rolls :
Immalor 11,3 one hits! for 5 dmg
Turin 1,9 one hits! for 3 dmg
Leon 19,11 both hit! for 4+2 = 6 dmg
Zavenorrin joins in with his bow, 19, 9 both hit! for 6+4=10 dmg
The ooze now mostly through the doorway slows it's pace. Several arrows protrude from it and sizzle as they dissolve. The sling bullet is lost within the creature. It slows and then stops.
After a few moments as you prepare more arrows and back up a bit you see it's form begin to harden and then crack in spots. Fissures begin to form. It appears to be 'dead'.
What are your next actions?