Sure, everyone can roll a Stealth check for me.

Stealth: 17

Thelanis moves clumsily down the corridor to the dismay of stealthier members of her party.

[[Stealth: 13.  WITH Pass without trace.  Rolled a 1.😜]]

Amiz trust in his friends magics even though he is not one for stealth most of the time he will give it a go. 

9 + pass without a trace =19

Ok that'll do, you sneak into an open room and are able to hide behind some barrels. Torches hang from the wall at intervals and there is a grand table at the far end. A rope ladder hangs in the middle of the room going up to a chamber above. Seated at the table are 4 figures. Three of them look similar to the zombie hobgoblins you fought at the mine entrance, while the fourth is quite different. This one sits at the head of the table and still wears his armour. His previously red skin has turned a sickly pink and his features are sunken and hollow. On this undead hobgoblin's back is a large single bladed axe. The elegant elven looking axe has a dark red tinge to it's metal.

Are you going to spring a surprise on the undead hobgoblin's or do something else?

Thelanis intends to engage the undead hobgoblins from stealth with range attacks, then close in.

Ok you can all take a surprise round.

There's three hobgoblin zombies and a more ornate undead hobgoblin with a huge axe sitting at the table.

Valar will Suprise attack the ornate zombie with the axe Attack: 21 Damage: Unable to parse dice roll.

damage 8

Draíocht eyes the axe-wielding hobgoblin at the table. His eyes furrow at what he assumes to be the elven artifact in the hands of an undead monstrosity. He looses an arrow at it and then forms himself into the shape of a dire wolf.

Action: Longbow @ Ornate Zombie
To-Hit: 19+5 = 24
Damage: 7+3 = 10 piercing

Bonus Action: Wildshape into dire wolf.

Amiz and Thelanis will attack one of the zombies at the table with their axe and Eldritch Blast.

Amiz Axe against Zombie 1: Attack: 10 Damage: 9 Slashing

Thelanis Eldritch Blast against Zombie 1 Attack: 19 Damage: 10 Force

The Zombies all attack their targets, splitting between Amiz and Valar. At the same time you get a haunting feeling coming from the area up above, as though a chill wind is about to whip you from behind.

Ornate Zombie Axe 1 against Valar Attack: 20 Damage: 11 Slashing

Ornate Zombie Axe 2 against Valar Attack: 18 Damage: 7 Slashing

Zombie 1 Slam against Amiz Attack: 19 Damage: 5 Bludgeoning 

Zombie 2 Slam against Amiz Attack: 17 Damage: 7 Bludgeoning 

Zombie 3 Slam against Valar Attack: 17 Damage: 5 Bludgeoning 

As the axe bites into Valar, he feels a furious energy ripping through him, threatening to send him into a rage at any moment.

You all are up, Amiz and Valar engage the zombies, while a chill energy whips at Thelanis and Draíocht's backs.

Amiz is furious that he was actually hurt by this shambling dead. He swings his axe intent on permanently killing these cretins

Axe

Attack: 23 Damage: 12

Zombie 1 is downed, DC 19 Con Save to stay up: 9

Zombie 1 is down.

You other three are still up, 2 zombies and boss zombie still alive, while a strange noise is now getting closer from the chamber above and behind you.

Draíocht hears the strange noise. Certainly they'd see what it was soon. Probably some undead monstrosities from those necromancers. He charges forward towards the ornate zombie to snap at it.

Bite @ Ornate Zombie
To-Hit: max(13,18) + 5 = 23 //advantage from Pack Tactics
Damage: 3+5+3 = 11 piercing
Ornate Zombie makes a DC 13 STR Saving Throw and falls prone on a failure.

(I think I need to go have words with blacksmith and see if he used paper in the construction of this armor...)

Valar continues the attack against the Ornate Zombie: Attack 5, damage 5

Thelanis closes with the ornate zombie, cursing it with necrotic energy from her blade. She launches at it, hoping her and Valar together can take it down before whatever is above us attacks.

BA: hex
Longsword: Attack: 12 Damage: Unable to parse dice roll. plus necrotic from hex 4