"If the door is locked, I wonder if someone might not still be at home. We could try calling out before risking a thousand and ninety-nine years of burning and freezing." 

Osmord stands before the rune covered door and begins the ritual to cast detect magic.

"In just a moment, I will be able to see... if magic is here."

Seeing Osmord casting,  and agreeing with the others- Arisa calls outside the mysterious door.  “Hello- is anyone home? We are not goblins or giants, just travelers from Waterdeep trying to find survivors!”While Osmord  finishes his spell, she will search the other cottage, pausing briefly  to say some quiet prayers over the dead halfling.  Perception 13

Casting his ritual spell, Osmord detects the presence of Evocation magic somewhere within the cottage.

Arisa calls out, but does not receive any reply. She then searches the other cottage that apparently belonged to the halfling family, and mostly sees the usual decor and items normally found in a village residence. From the gardens, flowers, many flowerpots and other items, it does seem the whoever lived here might be an apothecary. 

"There is magic here.... hmmm, evocation magic. Elemental force."

Osmord steps up to the house tries to break a window with the back of his dagger. Attack: 11 Damage: 2

(If the window breaks he will send in worm to take a look around).

Seeing what Osmord is up to, Belkas moves farther away, near Arisa, awaiting the promised explosion of infernal flames. 

With enough effort, Osmord is able to bash at the shutters and break one of them loose, creating a big enough opening to let Worm fly into the cabin. Fortunately, when the bird disappears inside the cottage, he is not engulfed in any kind of flaming explosion. 

Osmord

"There is no danger, there is a chest to explore. I think I have it."

Osmord will ritual cast unseen servant and have it open the chest. 

[If the chest opens without incident the servant will bring over the contents and hand them through the window, if the chest will not open it will either try to unbar the door from within or hand the chest through the window]

"Hmmm strictly speaking, we did not enter this place and all should be well."

Vernon silently asks Mielikki and Flandal Steelskin for protection, getting a strange urge to go touch Osmord when the ritual cast is complete. He walks up and softly blurts "Illikeim!" as he taps Osmord's shell. (Casting Resistance) 

Osmord casts his Unseen Servant inside the cottage, and then commands it to open the chest. Fortunately, the chest is not locked, nor is it trapped with any kind of magical ward, and when the servant returns and hands him the three items found in the chest, Osmord sees that one is a golden holy symbol of Asmodeus (worth 75 gp), one is a healer’s kit, and one a potion of healing. He realizes that it is the potion which was giving off the Evocation aura.

"The Lord of the ninth... a surprise to see you here. This explains the runes." He places the statue within his shell for now.

Osmord hands the healing potion to Vernon, "Here... For the next time... you try to tame a wild worg. A healing potion."

The healers kit he hands over to Arisa, "This may be of use? More so in your hands than mine. What more have you found?"

Arisa thanks Osmord.  “Indeed this can help us, thank you.   These people were apothecaries or herbalists, judging by the gardens.  I am trained in herbalism- with enough supplies I can even make potions like that one, and antitoxins, as well as popular but less practical teas and medicines.  I am seeing what is here, and if anything can be of use”.  She pulls a leather bag from her backpack which has collections of pouches carefully labeled with various herbs.   She puts the things she collected from the garden while Osmord was casting his spells into the pouches.  
She takes the healer’s kit and packs up it and her herbalism kit into her pack.   

"I too have such skill. Father taught me many things... before I ate him. Perhaps together we may discover new lore and achieve great power." Osmord offers a warm friendly smile, delighted to have found such common interest with one of his companions. As they move on he reaches over and takes a few choice cuttings to add to his own supplies.

Vernon carefully places the healing potion in his backpack as he continues to ponder what that spell was. "I hope the next thing I tame is more like the tressim than the worg."

Osmord chuckles, "It is a fine pet, but not perhaps a proud steed... my thanks for your spell." Osmord taps his own shell where Vernon had cast the resistance spell and smiles.

Belkas brightens as he sees Worm return unburnt from the house. As they head out to search the other buildings, music quietly fills the air around him, and he softly sings:

    And the Raven, never flitting, still is sitting, still is sitting
On the bust of Drasek Riven just above my chamber door;
    And his eyes have all the seeming of a Tortle's that is dreaming,
    Ghastly grim and ancient Raven throws his shadow on the floor;
And my soul from out that shadow that lies floating on the floor
            Shall be lifted — Nevermore!

Moving on, the next closest location to search is the east guard tower. It's a short walk from the two cottages, but as you approach, you notice that the door to this tower is ajar.

Arisa will listen outside the door for a moment.  “Should we send the Raven in?” She says to Osmord.

7 perception.  (Lol) 

"Oy, mate, might grateful fer all ye' did back thar'. But if'n I had a favor ta' ask ye, t'would be nae ta' eat me should I fall." Zyllith quipped back jokingly at Osmord after he mentioned eating his father, then followed along with the others as they all continued exploring.

Once they reached the east guard tower, the opened door raised her suspicions once more. "Aye, best ta' be careful 'ere, jus' in case." With deft silent movement she slide up to the edge of the doorway before carefully taking a peek inside.

Stealth - 16+9 = 25

Perception - 10+3 = 13

Vernon will touch his forehead and say, "Illikeim? Ikkileim?" Noting the fibrous effects as he says it correctly, casting Resistance again.

Edit: fixed tags.