Well, it's just the same. Sky Sanctuary does NOT have two acts! (It only has 1) So, here is the picture of 'act 1' of Sky Sanctuary.

After winning in Hidden Palace, you will enter the teleporter......





If you loved fighting Knuckles in the Hidden Palace zone, you going to enjoy Sky Sanctuary. In this stage, you get to battle Metal Sonic high up in the clouds! But beware, as this would be the last stage for Knuckles ONLY, it will be quite difficult for those playing Knuckles ----- for you will have to fight not only Metal Sonic, but also SUPER metal Sonic. Don't fret, it's not that hard actually. For Sonic players, you only fight Metal Sonic at the last part. Even though this stage has only one act, it has three bosses for you guys using Sonic. About this stage: there is only one badnik which is a 'copy' of Robotnik with jet boosters, only that is has a metalic head. This guy shoots laser beams.
There are quite a number of tips so click on this sentence to view them.
Midi file for Sky Sanctuary.