Imps are simple creatures, he keeps going straight (North) towards that entrance, passing the East opening for now.

As the Imp continues North...

A bizarre sight greets you in this rough-walled chamber. About a dozen giant toads with thick, mottled white hides are at work here, scribing strange writing into the ice of the walls, or onto weathered parchment and stone tablets. A few toads transfer parchments and tablets into and out of floor-to-ceiling cubbyholes cut into the ice along the entire southern wall.

A single tunnel leads out of this chamber to the East.

He’ll continue on his way East. The dragon is what he’s mostly looking for.

Down the Eastern tunnel here the imp finds what must be the toad's sleeping chamber...

This freezing, miserable chamber makes a perfect home for the ice toads, but is presently empty. None of the toads’ belongings here has value as loot, but they make a strange and curious collection. Such objects include walrus-tooth wart scrapers, spears fashioned from narwhal horn, oddly shaped furniture sculpted into the icy floor instead of rising above it, writing implements carved from baleen and shaped for a webbed hand, and art objects that combine carved whalebone, driftwood, and mundane items such as silverware and glass stoppers salvaged from shipwrecks.

There are no tunnels leading onward from here. The imp backtracks to the large chamber at the top of the ramp, where the single Ice Troll stands guard. The imp goes East this time from there... The tunnel to the east runs down at a sharp angle.

Though this chamber is deeper than the adjacent caverns, no mist hangs in the air here.

Three shelves stand in this otherwise empty cavern, cobbled together out of salvaged wood, whale bone, pieces of giants’ armor, and even the frozen limbs of yetis. A number of scrolls, books, parchments, and folios are carefully arranged on the shelves, all bearing the markings of magical writing.

Near the western end of the scriptorium, a 15-foot-wide chute leads down.

Leto will explain everything he has seen so far to the group and direct his imp down the shaft. 

"How good is your imp at looking for traps?" Honor asks, notably suspicious.

“Not great” Leto replies “He’s just getting a general lay of the land. At least now we know there is another troll and and a bunch of giant frogs... Though he’s still on the search for the Beast him((her?))self.”

"If we know where they are," Naivara says, "it'll make it easier to sneak around if we can."

The imp flies down the chute, coming out above a large ice shelf, covered with treasure, most of which is frozen inside the ice shelf itself.

Leto tells him to look around the room for any sign of the dragon, and continues to share this information with the group.

the imp looks around from atop the ice platform. It sees a large open area to one side, twenty feet below the platform's top. There appears to be a small pool of water at the far end of this open area, but the imp does not see any dragon.

Bac the other way the imp finds more rock platforms, some nearly as large as the first one, but with cracks between that lead down into darkness. Nothing else sticks out to the imp.

? What is the group doing? Moving towards the troll or what?

Naivara gets up. "Well, can't wait much longer..."

"Right. This should go much more smoothly, with one troll instead of eight. Hopefully we can catch the thing by surprise."

Kierro takes the front of marching order, unless anyone wants to stealth ahead, and moves cautiously through the tunnels to where the imp saw the troll.

Honor follows, sticking to the middle of the group.

Leto nods and follows along, also staying near the rear, and keeping in mind what he’s seen. Before bringing his imp back he directs him to take any random piece of treasure from the room that is sticking out. This is more to if there is any reaction than for the treasure itself, so he’s still ready to pop his imp into the pocket dimension should he be in immediate danger.

Latrius follows the rest, as invisible as usual.

Stealth: 27

If you want to take the troll by surprise we need stealth rolls. Is anyone casting pass without trace?

Naivara takes the moment as they get ready to go to use magic her mother once taught her to make them harder to notice as they move.

Cast Pass without Trace

Naivara Stealth: 36

Vale Stealth: 32

(Might as well at least attempt stealth.)

Kierro stealth + Pass w/o Trace: 20