A 3D engine by Damizean and Mark the Hedgehog, both of Sonic Fan Games HQ. Despite being a small engine test, this may be the best 3D <I>Sonic</I> engine I've ever played around with - just look at how the momentum works very, very much like the 2D games. Loops are obstacles that you can't go around without the right velocity (although the level design presently just lets you walk around them, but still). Practically anywhere in the level can be reached if you have the patience to build up the exact amount of momentum needed to get there. And while the level design <I>is</I> presently a linear path above a bottomless pit, it's opening the door for something a lot better.
<a href="http://tinyurl.com/2wem94">Download it</a>, play it, and spread the word - this is more like how 3D <I>Sonic</I> should be done.
<li>W, A, S and D = move (think first-person shooter)
<li>Mouse / Arrow Keys = move camera
<li>Left Mouse Button / Spacebar = jump
<li>Right Mouse Button / X = Hold and press jump to Spin Dash
<li>F1 = respawn (for when you fall into bottomless pits - which WILL happen if you're goofing around)
<li>Left Ctrl = deactivate fancy water (if your FPS is somewhat reminiscent of a decent computer trying to run <I>Crysis</I> at max)
To run the Green Hill-esque stage, go into the Stages folder, and edit Stages.xml. Change 'stage folder="Stage1"' to 'stage folder="Stage2"' (or vice versa if you're changing it back). Save, and run the program again. You should be in the other stage when it starts up.
<li>Damizean, Dimension Warped, Mark the Echidna, MistaED, Streak Thunderstorm, and The Taxman for creating this.
<li>Music by Jun Senoue, remixed for <I>Super Smash Bros. Brawl</I>
<li>Video by Shadow Hog; created with a trial version of FRAPS and Windows Movie Maker (because I'm too cheap to use anything better).