Boss for a MM fangame I'm heading.

[Tuna Unleashed]

Well, final boss actually. So, I'm new here. Hi.
The flail is slightly out of date BTW.

[Lazycow]

Looks nice, especially this giant bat-like-guy (or what is he?). As he is so big, some anti-alias could be fine here. And is there a chance to see some of these as animated gif?

[Tuna Unleashed]

I would've added a bit, but he'd already hit the colour limit. Oh, and yes, there is a chance. But there in an "easy to be put into GM" form so a lot of them will be separated.
Intro-
Idle-
a-
Run-
Jump-
Dash-

[Yo-Yo-Master]

Here's my suggestion for a change on that axe attack.  The dust clouds and ground shaking at the end are just my little preference, ignore if you don't care for them.  Please ignore the white junk on the axe; it is there due to my craptastic rotation tool! 

Imo, the axe needs more weight.  He should have to swing it back further to get that much of a swing, even if he is super powerful...

Also, in yours he sort of jumps forward and then is suddenly back a few feet when he smashes.  Maybe make him jump forward more?  I know in my edit, he kind of floats up (but hey, he can fly..), but keep in mind that the player will need a bit of time to register that he is using that attack, so they can get out of the way!

[Tuna Unleashed]

whoah, that's awesome. Thanks, I'll work with that, but with pixelier rotation.

[Yo-Yo-Master]

Sure thing.  I have some questions out of curiosity/perhaps to give further critique. 
Does he (it?) have some sort of theme like most Megaman bosses?  Right now I see...pointy things, energy bolts, fire, lasers, and dark physical.  That's a lot.   
What purpose does the roll have if he can fly?  His stationary idle is in the air, correct?
What is that a^/aerial a^ attack?  He turns into some kind of tiger pharaoh spaceship?   

[Tuna Unleashed]

He doesn't have a particular theme, since he's a final boss. He fights using  transforming gauntlets. The roll is for after he gets knocked down. Yes. It's like some kind of... lion sarcophagus or something. Any other questions about the game can be found throughout http://z4.invisionfree.com/NCFC_Megaman_Project/index.php?act=idx forum.

[Tuna Unleashed]

Well I fixed the outline.

[Yo-Yo-Master]

Yeah, the reason I didn't fix the outline is 'cause it was just an edit.  It wasn't supposed to be any sort of  final product, but more of a suggestion to show what weight can add to that type of attack. 
As for the axe outline, you still could clean it up a bit, something in this direction:

[Tuna Unleashed]