Dexter shakes the hit off and looks at his situation. The abomination between him and Ryn seems to be in bad shape, he may have the opportunity to take it out, but if Ryn can handle it himself he might want to be more concerned with the one that moved behind him to replace the one he had banished just moments before. Either way though, he certainly does not want to remain between two masses of tentacles.
Dexter picks his target carefully, sets up his attack, and strikes as best he can, balancing the need to end this quickly with his desire to be in a safer position.
(If Rynvoor does more than 6 damage on his next turn but does not finish the darter off, mark Darter 1 as my quarry if it isn't already, use Fading Strike on it, and shift NW, W.
If Rynvoor does less than 6 damage or misses, use Evasive Strike instead of Fading Strike and shift W, SW, SW.
If Darter 1 is already dead, shift NW, mark the darter currently NE of me (due E after the shift if it doesn't move) as my quarry, and use Twin Strike with the Longbow, both shots targeting that Darter. If I am not the closest player to it, though I should be with only 1 empty space between us, remove Prime Shot's +1 bonus from the to-hit roll.
In general, if you're not sure that what I'm attacking is my quarry, use a minor action to mark it as such before the attack.
Also, heh, exactly 10 rolls. )