pastel
I'm surprised this was never mentioned:
Special Stage (Sonic 1)
Hidden Palace Zone (Sonic 2)
This one is a little less obvious:
Final Zone (Sonic 1)
Final Fever (Sonic CD JP)
Special Stage (Sonic 1)
Hidden Palace Zone (Sonic 2)
This one is a little less obvious:
Final Zone (Sonic 1)
Final Fever (Sonic CD JP)