Ever wanted to know why Green Hill Zone in the Nick Arcade prototype is so broken? Well, when we take a peek at the collision map... oh dear. [Technical explanation in replies]

This animation does exist in Sonic 3 A.I.R. and Sonic Origins S3K. The latter, however, is a slight bit different than the original game; You have to be a bit closer to Knuckles to trigger the animation.

Under the Surface of Classic Sonic Even in the mobile remake, spikes and explosions are colored weirdly underwater (Sonic just got hurt, hence he's invisible).

Update: I moved this into a GitHub repository instead: github.com/devon-artmeier…

The original 1993 version of Sonic CD has a hidden tag object for propelling Sonic into a ball (typically used for tunnels) placed right on a spring in Stardust Speedway Act 2. This tag object is missing in the 2011 remake.

You can SLIP PAST the first puzzle in Marble Zone. You do this by jumping right next to the Spike Trap because Sonic's position has to be directly over an object when you jump on it otherwise you won't land on it #SonicTheHedgehog #SonicPhysicsGuide