Sunday, February 24, 2019

Took you long enough

25 years ago to this day, the original Sonic 3 was released for the Sega Mega Drive across European territories. Being from Portugal myself, I still have a full boxed copy!

In celebration of this date, I am proud to announce that a disassembly of Sonic 3 is now available, more than ten years after the original Sonic & Knuckles disassembly was released.

...Wow, I don't even know where to begin. Just five or six years ago I was still exclusively messing around with graphics stuff, afraid to touch any of the scary assembly code. Before I knew it, I was programming entire objects from scratch, writing a blog which is at least 50% assembly code, massively improving the level editor experience, and now this.

None of these things would have happened if not for the people at my side each step of the way. My undying gratitude to Tiddles for always supporting me and getting me on this wild ride. Thanks to MainMemory for always being there to talk and share war stories. Thanks to the readers of my blog for the motivation and for showing interest in a Sonic 3 disassembly. And ultimately, thanks to flamewing for graciously approving my pull requests to the skdisasm repo.

I hope you will continue to support me in my future endeavors. The ride's not over by any stretch of the word.


  1. This is amazing! I can't believe that it is finally here!

  2. Hi, As a small but big fan of Sonic 3, I'm very impressed with all of your works and efforts here! Sorry to leave a comment here, but I really can't find where I can ask a question. Here it is: Could you please figure out why we can't proceed to Mushroom Hill zone if we defeat Knuckles' boss while in Act 2, but why we CAN if we do while in Act 1?

    1. Yeah, it's never in a place where people might find it.

      Long story short, it's due to the background event flag at RAM address $EEC6. It's set twice but needs to be set three times, and the level results object just happens to set it when the apparent act is 1.

      Not sure I can write an entire blog post about this, so if you want, we can discuss this somewhere more suitable for chatting?

    2. Thanks for such a fast reply! Nope, please take it easy, I just wondered and didn't want to take your time :) I'll investigate myself with the address!

  3. Finally I found a place to make this question
    There's something that always bothered me in sonic 3 with super sonic
    Why SS can't use the insta shield? Or why you can't use the insta shield with normal invicibility.
    I'm not sure if that's a bug but it feels odd since the rest still can use their special moves as super but sonic can't

  4. This comment has been removed by a blog administrator.