Tuli and Arkan sneak silently into the room, noticing a heavy smell of goblin sweat. There are three total goblins; one looks rather beefy, like the large goblin the group fought outside, while the other two are a bit scrawny.
Arkan points to herself, then to the largest goblin; then to Tuli, and to the next largest goblin. The message is quite clear, and Tuli heads over to the smaller goblin while Arkan moves to the largest goblin.
Each of them unsheathes their swords and, simultaneously, they plung them into the most sensitive spots of their adversaries. The larger goblin awakes momentarily with an ear-splitting scream, then falls limp. The smaller goblin, however, wakes as Tuli plunges her sword through, then grasps the sword and attempts to fight back.
The scream has also woken up their friend, who nearly hits the ceiling as he sits up in the top bunk, startled. He scrambles for a weapon.
OOC:
Actions, please? I'll post init shortly
Notes:
Manzanita: You'd all but said "coup de gràce"; I figured I'd give you the most favorable situation possible. 
For the record, Arkan hit for 2d8 + 8 = 20 (6+8+8) points of damage, and the larger goblin couldn't have made the DC 30 Fort save.
Tuli hit for 2d6 + 1d6 = 8 (1+3+4) points; that goblin made his Fort save (roll 17 + 4 = 21 vs. DC 18). Of course, he's lost a few HP...)
I've made some assumptions about actions here to get things going; let me know if this isn't what you would have done.