Unchained Missiles
If you'll indulge me a bit of absolutely nonsensical tinfoil hat-ness (and Metroid geekery) here...
I know I've mused on this before, but it must be said again: Sindragosa is the Ridley of WoW.
Think: big freaking bony dragon, penultimate boss, encounter is a great deal about crazy ranged DPS. Even her entrance into battle reeks of Ridley!
True, Sindy is significantly chattier than Ridley. But she's got that same sadist streak (understandable considering she got shafted hardcore as Malygos' former consort). Of course, if you want to split hairs, I'd say she's more like the X-Ridley in Metroid Fusion, since both are more or less zombies~
Yoshi and Leslie have thus far been the only ones to take her on (and only Leslie has been able to footstomp her). I was kinda hoping Rei would be the first to kill her, since Rei is a hunter and, well, some in Across would claim her root character draws a touch of inspiration from Samus. Oh well. All the same, I gotta rock some flavor of the Ridley fight theme (either the original Meta Ridley from Metroid Prime, or the Brawl remix of it).
You know what would be stupidly funny, though? Rei ought to bust out some crazy, presumably-Goblin Engineering-made oversized rocket and fire it right into Sindragosa's mouth as the killshot. I'm totally serious-- it'd be her freaking Super Missile. :D And if you've played Metroid: Zero Mission, you would know that Super Missiles were ridiculously overpowered (perhaps intentionally so). This almost makes me wish Blizzard wasn't axing ammunition with 4.0.1. Of course, this doesn't rule out adding some kind of "super rocket" item (perhaps as a new ICC craftable for Engineers to replace the removal of their ammo?). That would be fun, too-- an Engineer-only crazy missile, and a second, less-powerful version that could be used by anyone.
...the "Sindragosa = Ridley" thing brings up another question: who would be considered the Kraid of WoW? I almost want to say Rotface and Festergut fill that role.