Ellren, after observing and analyzing the situation for a minute, finally decides to step up and without saying a word (besides the spell) casts Burning Hands.

OOC for DM: Each creature in a 15-foot cone must make a Dexterity saving throw. A creature takes 3d6 fire damage on a failed save, or half as much damage on a successful one. The fire ignites any flammable objects in the area that aren't being worn or carried.

So dont use AC; any creatures (including PCs and NPCs) within the range have to roll a d20+Dex Modifier, if its below 13 then they fail the save and take 3d6 fire damage.

Also, just a sidenote: dont tell us the AC :) let us roll for an attack (d20) AND damage in the same post. Makes it more mysterious and suspenseful and keeps us in character cause our character wouldnt know how easy or difficult it would be to hit the enemy :)

The Displacer Beast, smaller than expected, was quick to react as it realized it was targeted by a spell, and dodged away before the spell was even resolved.

Outside the cave, yelps and cries can be heard echoing into the cave.

The small Displacer Beast gave out a roar. Curious, the roar was not that strong, but it was enough to start the cave vibrating as such, the roar echoed throughout the cavern, resonating as if the entire cave was one giant instrument.

Eraqrin yells to everyone else, "I think that was a call for reinforcements! Get ready!"

T'ohra growls, angry at the circumstances. "Needs must I suppose, but I'll not let them say they didn't hear the thunder." With that she'll cast Thunderwave at the beast.

DC13 Con Save Damage: 8 Half that on a successful save.

The Displacer Beast, aided by the shadows, simply moves out of range of the attack. Nothing seems to be effective so far against the creature.

As Eraqrin's warning predicted, another Displacer Beast, this time a fully formed adult, had run into the cave, looking agitated and annoyed.

It was followed by a troop of more goblins, numbering at least six, with a larger goblin running up the rear, "Damnit!" the Hobgoblin roared as he saw the adventurers. "I thought the beast was enough, now we have to contend with these... fleshies!?" It said in common.

The lone goblin with them then reacted, "SMEE IS HERE!" He tried to call attention to himself to the Hobgoblin.

The cave seems to be crowded. The juvenile Displacer Beast at the farthest, trapped between the adventurers,  the adult Displacer Beast, and the goblin troop.

What you guys wanna do?

Ellren will yell out in Undercommon, "Attack the beast, and we can all walk away from this!" And I'll proceed to cast Magic Missle at the Displacer Beast. I think magic missle automatically hits and there's no save but feel free to correct me if I'm wrong. Here's the 3 damage rolls

5

3

2

Eraqrin will charge the smaller displacer beast with his flaming greataxe and slash at it violently, screaming all the while to scare everything off.

9 attack roll

Eraqrin's attack came with a force, the smaller Displacer Beast was too distracted, seeing the other Displacer Beast and calling out to it.

Eraqrin's attack sent the creature skidding through the dirt. (Roll for damage)

Ellren' spell came in combination to hit.

The smaller Displacer Beast is prone. Seems the creature was already much injured initially.

The larger Displacer Beast roared in concern as it saw the smaller beast being beaten.

It was distracted enough not to see the attack of the Hobgoblin which sent it crashing to the wall with the swing of its warhammer.

The smaller goblins all attacked the adventurers with tranquilizer darts targeting; (Tell me if Im calculating wrong)

DifferentNoodle 8
SaprothOrphanwood 11
ArmoredGull 23
GrimReaper17 10
BG05 19
DizzyBuriito 16

Damage: (greataxe + breath weapon fire) 21

Bramnus takes a swing at the smaller Displacer Beast with his war hammer: 5

War Hammer damage: 8

War Hammer Damage: 9

The goblins managed to hit three of the adventurers;

DizzyBuriito 5
GrimReaper17 8
SaprothOrphanwood 4

Saproth tries to dodge the attack, 

Dex Save 7

Unfortunately, the dart hit Saproth straight in the neck, and knocks him down.

Smee sees his opportunity and runs off his leash towards the other goblins.

On my turn I'd like to cast Shield which temporarily adds +5 to my AC

Re-rolling goblin dart on Saproth.

9

Damage if hit 7

Eraqrin pulls out his longbow and shoots an arrow at the larger displacer beast.

Ellren and Saproth both drop to the ground, incapacitated by the tranquilizers shot by the goblins. 

OOC: Eraqrin, roll for hit/miss, and roll for damage.

Attack Roll: 11

Damage if hit: 7