Damn, you're good. No hints at all. Correct! You're go.

I'll shed a little light on what you didn't get...

Echoed in an unheard sound. -->dunno bout this one!?
'Sound' is also defined as a channel, fjord, etc. The Gelinka wasn't in a channel, but it pertained to water.

For your blood we are so keen. --> they hav powerful attacks, and do some cause drain?
Poision-form of drain. (and trying to hint at monsters)

man, I spent a lot of time on that thing too, and you get it right off the bat. Dang. Made it too easy.