1) What ever happened to Hyper Sonic??? 2) Does Sonic Team have a good explanation for making the most recent Super Sonic appearances on the last level only (that's pretty lame)? 3) Are there any stages that can go beyond Hyper level (I can't find any comics so I don't know)?
1) That form's only in Sonic 3 & Knuckles.
2) Not that I know of.
3) Check the profiles section.

~ SA Tails