OK, Yalla and Rebecca stand outside the cave, you see a dale surrounden on all stie with mountains. In the middle of the dale, ther is a huge lake. You can see that in the other mountains are other caves as well. You can see other Orcs, govlins and bugbear moving around as well. There are 4 caves, including the goblin cave. As Rebecca moves outside she (and Yalla) sees a couple of goblins (5) going from the lake to the cave, with some bukets of water.
Yalla, you can now choose if you go on with your plan or not, if you go through with it, this will be what happens:
Yalla takes out her rope and creates a trap right outside the cave. She tries to camouflage the rope a bit. Then she crawls into the cave, she'll shoot an hide, shoot the leader with an arrow and flee (running out of the cave, hiding somewhere possible, avoiding to be tripped by the rope).
Yalla, your sneaking goes allright (rolled 8 and 9, with your bonusses). Once you are close enough to the king, you let loose your arrow, it hits him right in the stomach (14+14 (point blank) = 28, Hit, Damage 6+1+(Sneak attack)17=24) After that you easily outrun the goblins. You get 2 dagger thrown after you (rolled 13, 9, miss) Some 15 goblins go after you, the first two trip over the rope, but the other quickly catch on, and jump/step over it.
Combat will begin after this, the other members of the goup will hear a lot of angry voices form the cave, and understand Talla has begun her attack.