Alrighty. So, I'll choose to push Emilia the distance she gets from thunder wave, and then use her remaining movement to run.

Emilia bursts forward, the blast propelling her out of the reach of the beasts. She hits the ground hard and starts running (She is now 77 yard away from the gate)

Artun, GO!

Artan will use his 50ft fly speed to fail to pick up the nearest person (5 on a strength check) however he simultaneously will send a lightning bolt at the nose of the leader. Dex save dc16 for leader and anyone within 5ft of his nose. 11 lightning damage on a fail, half on success.

He will end up 15 ft in the air so that he's out of suspected reach. 

Leader's dex save: 7

Artun tries to scoop up Ember, but her twisting and dodging make it hard to grab her. He flies up, out of the reach of the snarling beasts

The leader manages to dodge some of the lightning, but its hair still stands on end as it gets shocked

Demetrius's Turn!

"Priestess, take heart!" he yells as he runs, casting healing word on Emilia at second level for 11 HP of healing. He dashes towards the gate, moving 60ft (50 yards away from the gate

Packs Turn!

Dex Save: 15

The pack stumbles as they run after Ember, but only barely.

The first group goes after Ember. Claw: 17 to hit, 23 damage. If that hits, make a strength save

The second group attacks Emilia. Claw: 23 to hit, 18 damage. If that hits, make a strength save

Two more of the beasts leap at Artun. Athletics: 23, 15

One of the beasts that leapt Artun both make the jump, and try to claw at him

Claws: 13 to hit, 13. If that hits, roll a strength save

Ember, GO! (you are 80 yards from the gate)

It hits. Strength save 19 (Nat 20) which I'm very glad about because falling off the broom would not be fun. 

(the hit depends on whether the shield is in play.  Ember will try to turn to interpose the shield, which may take some movement from her dash.  If she makes it, the attack misses.  If the thing gets her without the shield, it hits.  Let me know and I'll roll Str if needed)

Ember still dashes for the gate.

Ember runs for her life, the beasts taking a swipe as she retreats. Claw: 15 to hit, 22 damage. She is now... *math* 70 yards from the gate.

Guards Turn!

The two guards shoot at the beasts assailing Emilia. One of the bolts hit their target, causing one of the beasts to yelp.
Guard 1: 7 to hit, 11 damage

Guard 2: 19 to hit, 8 damage

Pack Leader's Turn!

The leader snarls at Beshlogs taunts, and tries to tear him to pieces.

Claw: 23 to hit, 20 damage. If that hits, make a DC 16 STR save or:

 Beshlog, GO! 

Str save: 12

Beshlog uses his reaction to cast shield and spare himself of the bit attack.

Having been savagely clawed, the massive wizard isn't in the mood to mess around. He casts misty step to remove himself from the situation and get 30 ft closer to the gate. Then, he uses half his movement speed to stand.

With his action, he casts ray of frost, at the pack leader, then uses his remaining movement speed (15 ft) to keep moving towards the gate.

Ray of Frost:

Attack: 13; damage 11 (cold). On the off chance that it actually hit, the ray also reduces the creature's movement speed by 10 ft.

The Ray of Frost misses, hitting to the left of the leader. Beshlog is now 50 yards from the wall.

Emilia, GO!

Emilia, now weakened from her own blast ringing in her ears and the slashes she receives from the claws, decides to make a break towards the gate. "Friends, for the love of all the Seraphim I can name, hurry up!" She shouts.

Emilia uses her movement to move as close to the gate she can, before casting guiding bolt with her action, targeting one of the beasts.

To Hit: 11 (+5 to hit normally, an additional +2 from her Amulet of the Devout.)
Damage: 18

Emilia's blast hits a beast in the face, causing flesh to bubble from the searing divine fire. The next attack against it has advantage. She keeps running, so close to the gate... so close!

Artun, GO!

(realised I never did a concentration check for the lightning when I was hit. Just rolled and got 13 so all good.)

Artan will cause another bolt of lightning to land by the leaders nose. Dex save dc16 or 14 lightning damage (halved on a save). He then flies towards the gate, but also up a further 20ft (35ft total), to be more out of reach. 

Dex Save: 17

Lighting comes crashing down as Artun's bulky form is silhouetted against the rumbling storm clouds of his creation.

Demetrius's Turn!

Demetrius runs for it. He takes the dash, moving 60ft. Plain and simple. He reachers the gate and yells at the guards "Open this thing up. NOW!" the guards start to comply scrambling to save the hope of the realm.

Packs Turn!

the group on which was attacking Emilia is momentarily dazed by the blast of thunder, but they manage to regain their senses and rush after Emilia. They manage to get a few swipes at her. Claw: 9 to hit, 8 damage.

The group which was assaulting Ember also attacks. After being denied by the magical bubble surrounding her for so long, they are furious as they attack (Ember still has shield up, since it lasts until the start of her next turn). 12 to hit, 19 damage.

Ember, GO!

(Sorry, is it "AC or higher hits" or "higher than AC"?)

Ember casts "Protection from Good & Evil" and dashes.

Ember, if it meets it beats. So if your ac is 21, then you are hit. Luckily, I rolled bad on damage

Guards Turn!

The guards frantically push open the gate. Right now, it is open enough that a medium or smaller creature could get through, but not one of the beasts, as they are the large

Pack Leaders Turn!

The pack leader runs after Beshlog, snarling in fury as it takes the dash. It pounces forward, right on Beshlog's tail.

Beshlog, GO! (remember, you will reach the gate this round if you move)

Beshlog, seeing the monster basically right on top of him, will attack it with his battleaxe and booming blade

Attack: NAT 20! (28 total); damage: 11 (magical slashing) + 6 (thunder). If the monster willingly moves before Beshlog's next turn, it takes an additional 14 thunder damage.

Then Beshlog decides it's time to book it and get to safety. He casts misty step with his bonus action, and uses his movement to cross the remaining distance towards the gate (if necessary... otherwise, he'll stay right inside the gate to help hold back the monsters).

"Well Rascal... that was exciting," the gigantic wizard tells the tiny critter with a smile.

Beshlog has made it into the gate! (also, NAT 20! Wahoo!). The leader takes a nasty hit to the face, gaining a new scar on its mutilated face.

Emilia, GO!