"Sure," Tryn exclaims and wanders over to place the coin onto Tymora's shrine, "I would be the last one to deny our lady of luck her due part!" Then he returns to the group, "Yes, why not warn more people. This looks like a fair job and it needs doing by someone. I'm all for Tharanau and Goraseth's suggestion. Let's see the gnomes and continue on directly to the dwarves. The earlier we warn everyone, the better."

"I am ready to depart!" Tharanau is excited to enjoy more adventures with this group. He feels he has chosen his companions well. 

While slow, Tryn’s step is firm and purposeful as he walks with his newfound friends out of town into a new adventure.

You set off for the travel rather early knowing the distant might take you about half a day. You reach the whereabouts of your destination a little over noon.Now you know to look for a stream. You follow a stream uphill to the base of the mountain, where waterfall erosion has carved out a natural concavity. The roaring waterfall creates a cloud of mist as it plunges into a shallow pool of water, within which rise two small islands covered with two-foot-tall red, green, and purple mushrooms. Several cave openings overlook the pool from rocky ledges twenty to thirty feet above. The mountain blocks any sunlight from reaching this place. That is what you have heard the Gnomegarde. 

You see five potential entrances to the caves marked with red arrows. Your characters can easily ascertain that every slope to the entrance might need sme climbing except the upper right arrow which has a little path carved making it easy way up.

"Any of you speaks Gnomish by any luck ?". Goraseth approches carefully the upper right place that could be the main entrance, looking for the presence of the gnomes. (Perception: 17). He leaves his weapon sheathed and speaks loudly in common "Good day ! Anybody home ? We are coming from Phandalin, under official duties, and are looking to talk with whoever is the leader here."

You hear a voice from behind you, one gnome emerged from western cave entrance rubbing his eyes. He answers irritated:

"Could you not be so loud ? some of us are having a nap here at the moment so please do mind that. Our leaders are occupied at this moment, i would recommend you to talk to Fibblestib and Dabbledob, they should be in the chamber behind the one i am in."

After speaking his words he turns back and vanishes in the cave.

Tryn shrugs when moving to enter the indicated cave entrance and whispers, "Well, let's go silently to that cave and let's see if those gnomes will listen to us." 

Tryn takes a few steps towards the cave entrance, before he stops dead, "How did they get up there? It would be mighty inconvenient for them to climb up that slope each time they get home, I would think." He looks around and not wanting to disturb the sleep of these good people again, he points to the path on the other side of the water flow, traces with his hand over the cave entrances to a bridge and, finally, towards the the entrance where the gnome had emerged. "Perhaps we can just walk up there and get to the cave the civilised way by crossing that bridge. Who knows? We might even find open ears to our warning on the way to Fibblestib and Dabbledob." Tryn crosses the stream and begins to ascend the small path.

"I agree. Let see how these gnomes can help with the dragon." Goraseth follows Tryn

Athletics: 23

As you walk up by the path you end up entering the cave where ceilings are no more than 7 feet. Even here in the tunnels the roaring waterfall is heard and it is making communication difficult, that you have to shout to each other. Caves and tunnels are illuminated by hanging oil lanterns attached to rope-and-pulley mechanisms. Exploring that entrance area you discover the dining room - This room contains several dining tables and chairs sized for Small folk. A stout wooden cabinet against the east wall holds tin dishware and utensils. tunnel to the north ends with closed door, and way south has doors closed as well, however east tunnels leads you to a cave with some strange invention - Parked in alcoves in this otherwise empty room are two gnomish contraptions. Each resembles a crab with a barrel for a shell, six articulated metal legs, and a pair of forward-facing pincer claws.

Tryn presses on towards the way that he thinks is the more direct towards the bridge (the southern passage, not the northern door). At seeing strange gnosis inventions, he simply shakes Zähigkeit head and prefers to keep them at a distance as to not inadvertently trigger any of the contraptions.

Tharanau follows Tryn tentatively through the tunnels. 
the gnome had emerged from the other side of the chasm with the water, so he feels that they should be going south if possible. 

Tharanau tries to figure out, if the south door has seen much recent use ( perception 16 in char sheet) and hints as to where they could possibly find gnomes that could help them. 

he is trying to stay well away from the barrel crabs, they certainly have an imposing look about them. 

« Very well, let’s head this way. Where are all the gnomes? that looks empty. Strange. » Goraseth continue, following Tryn .

The doors seem fairly used and not even having a lock. Listening in Tharanau can hear some occasional tools clinging and grunts, seems like someone is working behind the doors. 

Goraseth knocks on the door and enter the room without hesitation, throwing a loud "Good day !" to cover the tool noises.

You enter the room with Goraseth in front. Bolted to the floor of this room is a rotating platform equipped with four heavy crossbows. Mounted above the crossbows at a height of 6 feet is a chair on which a gnome sits.

The gnome sitting in the chair upon seeing you starts screaming and laughing simultaneously and reaches for the lever. 

Initiative order(i took the liberty to roll those for you):

Gnome on the crossbows machine: 18
Goraseth:13
Elrora and Tryncaryn: 6 (let's try that whoever post first goes first)
Tharanau: 5

(and since he rolled highest) Pulls the lever and you hear a loud release of a bowstring then the machine rotates and another one of the crossbows when it gets in position in front of your team unleashes a bolt in Goraseth direction. Goraseth thinking quickly and seeing the gnome reaching for the lever tries to shut the door in the means of defending himself which works as first heavy bolt hits the door nearly splitting it in two (as the doors were really worn of). The second bolt flies with such devastating power that it splinters the rest of the door and hits Goraseth who barely manages to put up his shield and thwart the potentially tragic blow and misdirecting bolt from any vital organs. Yet it still teared through the side of his chain mail injuring him badly.

Attack rolls are 9+5=14 and a natural 20.
Damage for the critical attack. 2+8=10 (there is no bonus that is 1d10 rolled twice since the critical)

"Cover !"
He did not anticipate that the gnomes would be hostile. What on Fearun was going on ?
Goraseth bleeds profusely but is still standing (1 hp left !). He assesses the situation quickly and decides to run toward the attacker. He remember fighting crossbow gladiator and he always use the fact that had a long reloading time to his advantage. He runs to the machine and tries to hit the gnome's head with the flat of his weapon (non-lethal damage). "Stand down gnome ! We are not here to fight !"

Attack: 12 , damage 8

You knock him down. The gnome is now unconscious.

Tharanau tries to hide his shaking hands. Going into a fight well prepared is one thing, being assaulted by a strange mechanism with a riding gnome on it, that was just frightening. And wow, what a close call for Seth! 

Nevertheless, he jumps into action right away, pulling rope out of his backpack and tying up the gnome. Then he'll check out the room more closely. 

investigation if needed: 12 on character sheet

Out of reflex, Tryn hid behind the first obstruction when the first bolt flew, which happened to be Tharanau. So that, when Tharanau moved to apprehend the crazy gnome, the halfling was left in the door frame staring into the room and still unsure if it is safe to enter. "What was that?" he asks Tharanau and Seth, "Why the heck did he start to fire? The first gnome was nice to us. Well, for a gnome, anyway." Prepared to dodge more projectiles, Tryn carefully enters the room and looks for any other contraptions and dangers.

Perception 14.