“Be on your guard, whatever burrowing insects or creatures did this, they may still be around, hiding just under the dirt.”  Anton takes out his collapsing pole, extends it to the full ten foot length and starts poking into the piles of dirt, looking for anything hidden inside.

Nico approaches the closer of the two piles of rubble and examines it; if there is a hole present, he'll peer down into it, then cast Light on a fragment of rubble and drop it down the hole to see how deep it goes.

You see something shiny....

and moving...

ROLL INITIATIVE! 

Nico's Initiative: 19

Anton initiative 9.

.

Razzec's Initiative: 3

Grey Initiative: 16

Hulk initiative 12

Ember 21

Nico 19

Grey 16

Hulk 12

Anton 9

Razz 3

-------------

If you have proficiency in Nature, you can roll it. If you roll 10 or higher you know about averting you eyes. If not, you have no idea.

NICO and GREY gogo!

[not prof in nature so he knows nothing]

Grey will move if needed to make sure the Hulk is within 15 feet of himself, and he casts Spirit Guardians.

At start of it's turn it must make a DC 16 Wis or take 10 Radiant, save for half.

Ember initiative => 19

Nature => 21   <<  Will yell out whatever the heck he knows to yell about while taking to the air.

Quote from Kol_Drake >>

Ember initiative => 19

Nature => 21   <<  Will yell out whatever the heck he knows to yell about while taking to the air.

 Umber Hulk

Probably most relavent - 

Confusing Gaze. When a creature starts its turn within 30 feet of the umber hulk and is able to see the umber hulk’s eyes, the umber hulk can magically force it to make a DC 15 Charisma saving throw, unless the umber hulk is incapacitated.

On a failed saving throw, the creature can’t take reactions until the start of its next turn and rolls a d8 to determine what it does during that turn. On a 1 to 4, the creature does nothing. On a 5 or 6, the creature takes no action but uses all its movement to move in a random direction. On a 7 or 8, the creature makes one melee attack against a random creature, or it does nothing if no creature is within reach.

Unless surprised, a creature can avert its eyes to avoid the saving throw at the start of its turn. If the creature does so, it can’t see the umber hulk until the start of its next turn, when it can avert its eyes again. If the creature looks at the umber hulk in the meantime, it must immediately make the save.

Forewarned, you can choose to not look but that also means you are fighting it blind and spells/features that require "target you can see" can't be used.

Seeing something moving up at speed from the hole, Nico cast a quick spell and appeared 30 feet away. He then focused on the weave and waited for whatever it was to appear, to snidely comment, "Nice try, you filthy bastard!"

BONUS: Cast Misty Step to teleport a full 30 feet away from the hole
ACTION: Ready a cantrip; he'll cast it as soon as the hulk appears, targeting it
READIED: Cast Vicious Mockery at the hulk; DC 14 Wisdom Save, or take 5 psychic damage and it has disadvantage on its next attack

Ember flies as high as possible in the hope of moving behind the Umber Hulk.

Looking down on the beast, he will cast Flaming Sphere to appear down next to the UH.
A 5-foot-diameter sphere of fire appears next to the Umber Hulk. 

Initial Fire damage:  6

Ember will use bonus action to move the sphere to keep bumping into the creature.

It is a 30 by 30 foot room.

Wooden door with a pull handle in the middle is on the  right side.

There are three broken holes in the walls - probably passages created by the umber hulk.

Ember needs to make a DC 15 CHR save.

Umber Hulk WIS save 6

Ember Charisma roll == Dirty 20

(game log)