Legend of Zelda: Skyward Sword [SPOILERS]

The only treasure i have problems getting is the Bird Feather. Those birds are so damn hard to catch!

So guys, which is your favourite boss so far in this game? as i said previously my favourite was probably

 Spoiler

Koloktos.
The battle with Tentalus had a really awesome atmosphere (the first part has you running through a sinking ship being attacked by tentacles, which was just bad ass) but the fight itself lacked, it was so plain.