Now armed with a torch and stashing his bow away
Trevor wades into the fray. Unbeknownst to him however the goblin takes a cue from this and subtly mutters a few words and makes a few hand gestures. As Trevore moves to engage the enemy he notices a feeling of warmth spreading through him as panicked looks appear on the faces of a few sailors he approaches who are fighting . As he swings at the creature he misses, rather badly, it still seems to have an effect as the creature begins backing off. Only then does he notice that so too are the sailors.
OOC:
FYI : illusions are usually small, not even person sized, so making the entire deck appear to burn is a bit far.
Add to that your roll is technically a fail, I turned it into a success at a cost, and the illusion is not quite what was intended.
Gutelos is at first surprised and please that his illusion is working as he felt the storm slightly disrupted that third word. Oh well. The magical flames dripping from the torch form a blazing trail behind the torch wielding bowman. The back of the man is now flickering with flames and slowly spreading across his back and begin to engulf the bowman.
The captain continues shouting orders and his officers rally the men to charge the fish-men. With half of the ship cleared and a crazed man who appears to have set himself ablaze the remaining Sahuagin make a tactical withdrawal, leaping from the ship into the waves, and a chear rises from the crew. Joining in Gutelos congratulates himself on the splendid effect of his illusion, as a pair of sailors grab a piece or tarp and tackle Trevor to the deck as other empty pails of water over the confused archer. Once satisfied the flames are out the sailors gently unwrap the tarp, slightly afraid of the flames effects, and are shocked to see only a confused and damp Trevor.
The captain quickly restores order to the ship and you are sent back below decks, with a couple of sailors, who remove all lanterns and torches, leaving you in dim candlelight as the ship tosses back and forth with less violence than before. One of the officers joins you as the sailors leave.

Emil
Casting a unreadable look at Trevor before speaking to all of you
Thank you for your aid, it helped turn the tide at a key moment.