Xanthas considers suggesting they use fire arrows, but doesn't see the sense in giving away their position. Besides, they've practically loosed them already.
Fear in his eyes Dylan stammers Sh-shh-shoot what?! What do you see that I don't!? The bard crouches low and looks about the sewer very much afraid. He makes to stand so he is covered as much as possible by the body of the group so he would be the last person to get hit should anyone/thing attack.
"Sh-sh-shut your mouth coward...and stand and protect the Lady," Xanthas says in a mocking but quiet tone. He turns to the elf beside him, having guessed his profession well in advance simply by his array, and asks "Do you have any spells to better our vision, Good Wizard?"
This should do, Lenya says, while stepping forward and touching Kinden's notched arrow, whispering an arcane incantation thereby. Soon after the arrow starts to glow and emit light.
If I only had wings like you, she says to Midnight quietly, while stepping back, it looks like the sewer gets deeper there... Lenya sighs and continues to watch what happens.
The glowing arrow from Kinden's bow and the non-glowing arrow from Shadowleaf's bow fly unearingly towards the ripple in the water and they both hear the arrows connect (thunk, thunk!). The disterbance in the water neither reacts or changes in anyway. Both elves can see the tips of flights on the arrows protrude from the... whatever, creating their own unique disterbance in the water.
The sludge that moves over the 'thing' is too dark for Shadowleaf to determine what it is. The sludge appears to absorb the light, being more mineral then liquid, or so it appears.