Song is the Ghirahim boss theme from Skyward Sword.
This is a Kaotic I encountered during one of my runs (KETF thing). It had an entire squadron of Tri-Wolves and Tri-Spiders with it. The name comes from it's ability: it seems to be able to heal any Kaotic, and also one other, how do I put this... unsettling... thing... I believe it has achieved sentience. It appeared to be directing it's underlings. And, judging from this and the crystalline protrusions on it's back, I think it spawns directly from the Kaos crystals, although that I cannot confirm.
