Ever wondered what it would have been like if Sonic & Knuckles worked with the first Sonic The Hedgehog? This hack answers that question, and it works with flying colors.

For those not in the know, the first Sonic game wasn’t compatible with the special S&K cartridge, but this didn’t stop rumors from floating around the schoolyard: cheat codes that didn’t work, absurd unlocking conditions, you name it.

The hack works as described: you get a fully-working Knuckles in place of Sonic, complete with a brand-new title screen. Spindashes, gliding, and wall-climbing all work beautifully, and the game plays exactly how I imagined it would.

Now you might wonder why someone would play this hack over the newer Sonic Classic Heroes, which does the same thing, but has the added advantage of including Sonic and Tails, a second team of playable characters, Sonic 2 content, level selection, and a save feature. Not that you can’t do both, but if you are building a curated library, I’d argue that this hack still has a place today for players who want a more “pure” experience that simulates the look and feel of playing a Sonic 1 cart plugged into a S&K cart, right down to the HUD, and it fits perfectly alongside S&K’ed versions of Sonic 2 and 3.

Overall, a great hack from Stealth that gets the job done, and does it well. Today, Sonic Classic Heroes may offer a lot more, but this hack still holds up if you just want something simpler in your collection.