Ooh! Boss fights! The part of any game I look forward to!
3) The Death Egg Robot in Sonic 2. I actually really enjoy this boss even though it isn't a very hard boss. It simulates stress because of the no rings deal, which I really like. More bosses in Sonic games should be like this, in my opinion.
2) Metal Sonic in Generations. YES YES YES! Now that's how you do a boss fight in a Sonic game! Everything in that fight is amazing! The remix of the Metal Sonic boss theme from Sonic CD as well as the whole fight based arounf high speed platforming as well as actually fighting Metal.
1) Solaris. As much as I despise Sonic '06, I love the fight with Solaris (Especially phase 2)! I love the phase 2 rendition of His World, the control and the atmosphere. Everything about that fight screams perfect to me. I think that that's how a Super form Sonic boss fight should be handled.