Trinity follows along.

"Be prepared for anything... Slippery squid dragged a part of this world ta ours just to get the rod. Who knows what else its capable of..."

Thorin nods and moves forward, trying as he may to remain unnoticed as he approaches the tower (Stealth: 20). 

The creature climbs higher and higher, before eventually ripping the bars off of a window and entering. As you continue approaching, four jackal headed creatures dressed in fine robes appear before you. "Halt there, Trespassers!" One of them hisses.

"Look, there, that thing is trying to steal from you, he stole from us, and this nice dragon, we must stop him." Trinity yells.

Persuasion check 16

Grix would try to add to the Persuasion attempt "You have a Morkoth loose in the realm...it has already infiltrated the dragon's lair and stolen an artefact, and it intends to do the same in your tower....how did you not see it?"  Grix has a +5 modifier himself, so either that gets added to Trinity's roll or she rolls again with advantage? 

The creature looks back at the Tower, noting that the bars on one of the windows have been removed. "Well so what? This beast you speak of is no match for us Arcanoloths." It says with a sneer.

"And what of the property of ours and the dragon?  He asked us to retrieve it for him."  Trinity spits.

(how do you want us to handel the rolls?

"I wouldn't be so sure! The coward is most likely gonna bend reality to run before ya even get close to it! Ya really think we're in this dimension because we want to?"

(I would say Persuasion. Maybe Deception, since you're basically conning them, but you're also telling the truth. So yeah, I'd say Persuasion.)

OOC: So assuming that someone is trying to give the Help action as part of the Persuasion Check can you confirm that it is a roll with Advantage or do you use some other rule?

Grix & Abz have a +5 modifier to Pursuasion - so it should be one of us making the attempt.  Happy to make the attempt if you all confirm.....

(Yes, with Help it gives advantage.)

Abzerilan is more than happy to help!

Quote from JumpierPoet >>

(Yes, with Help it gives advantage.)

 Assuming that the discussion to date has given rise to the check

Persuasion 18

OMG: I can't believe how bad Grix has been rolling.....sorry team

"We don't let strangers into the Tower Arcane. At least not for free. Make a deal with us, and we'll let you in." The Arcanoloth says. a sly smile crosses his face, as he eyes each one of you individually.

(OOC - don't apologise. These digital dice rollers always seem to skew to low rolls... always *sigh*)

"A deal? Have I got a deal fer you then!" Thorin says with a grin as he stands up tall and puffs his chest. "I'm no bard, but I've traveled the..." he looks around, "well, no here but traveled. Played in many a tavern an' pub. An' let me tell you, there's no rowdier party than a party with Thorin," he grins, pointing at himself with his thumbs. "Now I'm sure yer've no had much entertainment down here fer some time. So how about ya let me an' me friends in an' I can put on a show fer ya?"

"Hmm, what kind of 'show'?" The Arcanoloth asks, eyeing Thorin curiously.

"Improvisation, evidently..." Abzerilan says under his breath.

"Show? Drinkin', merriment, music an' dancin'. Ya do know how ta have fun, don't ya?" Thorin says in utter shock.

The Arcanoloths look at each other. "How can we be sure this is an even trade?" One of them inquires.