Hardest Boss Fight?

[Skyfrost.]

Last Boss on Phantom Hourglass took me eleven tries.

[Ad Bot]

[otto-san]

Last Boss on Phantom Hourglass took me eleven tries.

it was pretty silly yeah

[Regulith]

[Mega-Bear]

Bowser at the end of Mario Party DS. :c

[TheScout]

The final boss of the Internet.
loving difficult

[Rugged]

The final boss of the Internet.
loving difficult

wow noob i beat him first try

[Ector]

SA-X from Metroid Fusion.
First form, anyway. Second one's a cakewalk.

[Xinakam]

That. A thousand times THAT!!!

[Proog]

Majora's Wrath.

Not the hardest depending on how you fight it, but really stacked.
A closer examination. Check a bit before 9:00 for the other OP as stuff moves.

[Mushroom man]

Hardest boss I have faced was the bad guy for the Wii remake of Goldeneye. I may have been doing it wrong or something, but I never beat him.

[Unwritten Calender]

Mehrunes Dagon

But seriously, I'd have to say Coralis from Kameo: Elements of Power.

Wow, I remember that game..

[stuntman021]

Obvious answer.

http://www.youtube.com/watch?v=sQZuidKexBQ

your actual hitbox is like 1 pixel, so while that boss looks really hard it's not as difficult as you might think

[otto-san]

some Jamestown bosses are kinda hard

[Shortcut]

http://www.youtube.com/watch?v=Ek5963NgkWM This piece of stuff set me back 2 hours.