The spike glitch has always been really interesting to me. Obviously it was un-intended, as they fixed it in later games, but the reason it happens is kind of funny. In Sonic 1, you don't gain i-frames until after landing. Once hit, Sonic enters a state where enemies no longer collide with him, then once he lands he enters his normal state with i-frames. However, the spike uses the same collision as other scenery objects, so it's the 1 thing in the game that can damage you even if Sonic is in his special falling state, because naturally they didn't want him falling through the ground. I am not sure exactly how they fixed it, but either checking the state if he does end up colliding, or starting the i-frames right away but leaving the timer at 1 until he lands are both potential solutions. To know which one they used I guess you'd have to pay attention to if sonic blinks after getting hit before landing in later games.

The reason why the 255 is the highest number for Sonic's life counter is because it support 8-bit integer. If we go below 0, the integer underflows to 255, and if we go beyond 255, the integer overflows to 0.

Sonic 1 when it crashes: text telling you what happened Sonic 2 when it crashes: no information but it doesn't take that long for you to know what happened Sonic 3 when it crashes: what in the living heck happened to the universe?

the reason gaining +1 life from 255 effectively brings you to 256 is because when you're _at_ 0, losing a life brings you back down to 255, so you effectively have 255+1=256 lives. you normally can't be at 0 because hitting 0 lives via a death triggers a game over, but since you're instead hitting 0 _without a death,_ the game never bothers to check if you should game over, so you don't.

I love a good glitch compilation. Keep them coming!

6:51 i like the nod

23:02 Classic Sonic Simulator players: first time?

30:12 You could activate the slope glitch, which you could do on the original/emulator. That way, you can enter the top wall and finish easily

1:27 Glitch: No Hand No Two Legs!

This is very important to know! Thanks for showing these glitches. I am a member of a community that creates achievements for Retro Games (RetroAchievements) and this data will be precious for me to blocking the player using them to earn achievements - especially the zip strategy xD

18:27 Unless your in Debug Mode.

Nice, great game for glitching sake! 😆👌

Jumping at the end letting you retain control stayed a glitch in Sonic 2. 🙂

The 255 lives glitch: The real integer is -1, since the 8-bit binary code starts with 1, looks like this: 1111 1111 In hex, it's 0xFF.

Yes, there's a glitch in spring yard zone. The roller badnik appears using some pieces of the caterpillar from Marble Zone

The hate for Labrynth Zone really bugs me. It's not all that bad of a level, it's Marble Zone, but with water. I know that doesn't sound promising, but, it's still a fun level.

In marble zone you can actually push blocks by rolling into them so you don't have to hold the direction button. Don't know if it's a glitch or intentional. There's also something in spring yard that I like to call the inifinite skid were you if run down the hills you can hold sonic's skid animation with the waving hand indefinitely even as you bounce around on bumpers and ending when you even land on a solid platform.

12:18 that scared the shit outta me...

At 8:48 if you position sonic just right you can jump in between the spike thing, and the wall, bypassing the need to even push the block.

There's so much you didn't cover, but cool video. My favorite is using invincibility frames on lava to clip. As a child in the early 90's it was my mission to try to break the game and find all it's secrets. Use debug on the special stage, go outside and hold left until you hit the glitch wall. You can get 6 blue emeralds.

There's a glitch where if you unlock level select and open it fast enough you can glitch the sprites out and on the left side you can see this glitch as is just a visual glitch you can probably get this glitch on the second or third try. Im gonna call this glitch the selection glitch

2:22 June 23, 1991, the "Spike into more Spikes" incident

12:48 & 13:06 right, down & illegal instructions sonic 1!

if u hit the orbinort in star light, you go past the ceiling so the game puts u at the kill play at the bottom

You forgot the glitch stage, 1st go to the special stage then go out of bounds, you can see different stuff randomly placed, if you can go more out of bounds you will see the special stage files and if you go even more, it will make you go to the normal special stage.

There’s one glitch in Sonic 1 that you can’t get on a normal sega Genesis controller, if you hold left and right on a slope going up towards the right of the screen, sonic will moonwalk, but you have to be facing left before you do it, and if you press left and right next to a wall, sonic will rapidly shift from left to right in the first frame of his walking animation

The pit from final zone at end of the boss also works on android version

Minor note about the Demo Mode glitch: Holding a jump button during the end credits "gameplay" sequences has the same effect.

1:55 LOL THE SPIKES BECAME A TRAMPOLINE

The title screen being somewhat jacked up is either the emulator fucking up OR the sprite limit option being turned off (which most emulators have)

Scrap Brain Zone Act 1 has an easy clip and wall pull glitch I learned as a kid. Those moving giant rectangular obstacles coming out of the walls? Go up to the wall, face away from the wall, duck, as the obstacle retracts it will take you into the wall. Press left and it will pull you through the wall. Most of these trap you in the wall. I can't remember but the first bottom one might be a working shortcut.

50000 points does not give you a life in Sonic 1.

4:41 I got this cartridge

BRO NO WAY. IVE DID THE EGGMAN INFINITE LIFES ON ACCIDENT. Now it makes all sense.

The glitch that gives you 255 lives can be used in Chemical Plant Zone Act 2.

I seen some visual bugs on game over screens where the ring graphics get messed up and show parts of text

19:49 Up C Down C Left C Right C also works to activate debug mode

14:05 super smash bros reference

0 lives explanation: The lives number is represented as 8 bits. So when you lose a live from 0 lives, it keeps taking carries from the subtraction until it can't, so it went from 00000000 to 11111111 (255).

There is one in Marble Zone where when you are about to get chased keep walking before you get down and then your levitating

The 255 lives limit is due to of the limit of 1 octet (0 to 8) , if the game had 2 octets the lives limit will be icreased by 4 (i think is this)

1:18 Ok, yes. This does happen on GENS. Buts it’s not for every emulator. Some emulators (like KEGA Fusion for example) don’t have the bug, so it really depends of what emulator you are using.

My favorite one is the creature pit glitch and the most scariest one is the no scroll intro

What if you wanted to go to heaven, but God s- ILLEGAL INSTRUCTION$000000000069

Did you try running into it at 29:53 instead of slowing down? As seen in the A + Start video, Sonic runs into it, basically giving you a higher chance. Although you may have saw it, just a reminder

7:03 I have a hypothesis on why this happens and I don't know a lot about how sonic 1 works so if I get something wrong then that's why. Ok so the background changes how it moves with sonic and goes up down left and right accordingly. So what I think is happening is that when you die in water something in the code messes up and freezes the background until the level restarts. So when you get a game over it freezes the background and doesn't reset the background because the level never reset. Yet again I'm not coding expert and don't know much about how sonic 1 works so if I get something wrong you can comment it or propose a different theory on how it happens.

4:34 A+Start Collaboration!? Oh son of a glitch

I managed to get the infinite invicibility theme in Sonic Mania once (by accident, obviously), I have a video of it, it happened during my Tails' playthrought

1:16 The cave sound...

18:46 this happened to me I jumped to pit thinking "There is a wall that will stop me"

You said THE Any key. Where's that? Also, the emulator I use does Up+C Down+C Left+C Right+C then A+Start until Sonic is visible. You nailed the "Hold Down A and Start until you see Sonic" part. Just know the version that most emulators use is the one I mentioned. You also nailed Level/Act Select, so there's credit for that.

You missed one, which I call a level wrap glitch. When you use debug mode to go below the ground in labyrinth 2, and do a level wrap, about 3-4 seconds in, the game crashes and says, “ILLEGAL INSTRUCTION”

6:51 Sonic exe Title screen lol

The speed of the last cutscene of the original sonic CD animations has a weird speed up and slow down thing

I think the first time I fought robotnik i gave him 255 lives..

Sonic 1

On error screens such as 12:54 you can press a certain button and force the game to continue anyways.

Wow, i never would tought this game had this many glitchies, but even then, it's perfectly playabel, unlike his GBA counterpart which is a mess!

This also happens in the prototype version of the game

I miss games having attract modes

21:29 this itemless monitor is belived to be an ecxeption handler for monitors containing invalid objects

Well son of a glitch

16:23 That glitch also works on Sonic CD from Sonic Gems Collection

16:36 The same thing happened to me with some Coliseum Chaos springs in Sonic CD XD

The Spike and Drowning Glitch can be explained by Programming. When Sonic Drowns, the game says "Play this Animation." Which is Sonic's Drowning Animation. This Animation overrides the "Hold Pole" Animation. So far, so good. The Drowning Source code says "Take One life from Player counter." Still good. BUT. Here's where the mess happens. While the Drowning Animation happens, the game is ALSO doing the "Push Sonic" Effect. Which, causes the Glitch. As Sonic is NOT told "Do NOT move Horizontally while dying." As that Condition is, almost never gonna happen, Except in this case. So, Normally Sonic would play the "Floating" Animation when being pushed. BUT, we have a conflict. As the Drowning Animation is in action too. Then by pressing A, we interrupt the Drowning Animation because, Sonic is moving Horizontally. Then, we hit Spikes. Because we have no Rings, that means "Die." So, now, we have the game with a "Stack" of things to do. Sonic Drowning Code says "Take one Life." AND, the Spikes with Zero Rings says "Take one Life." We hit a problem. One Minus Two, is, negative One. BUT, the Integer is not a SIGNED value. AKA "Can be negative." Why? Because if lives ever reached Zero, Game Over. So why would they developers care if the value became negative. That, won't happen, right? It, does. So. The game says "Well. I can't have Negative Numbers. So logically, the next number is, 255" This is referred to as a Buffer Overflow. This kind of thing happens in other games too. Like Twilight Princess on the Wii where the game says "Horse name can be up to 8 Characters." BUT, if you were to manually edit the save file and make it longer then 8 characters the game won't stop, and could load, 3rd party code. That is a Buffer Overflow Exploit. Fun times with limited hardware.

Yeah Fug u makes me laugh every time also if these were in sonic 1 mobile it would work better right

20:49

scared me when the illegal instructions showed up on the genesis mega mix

1:06 wasnt expecting that

1:27 glitch 2 no hand

the "sonic is fucking floating"is easier with springs just spam a b or c in any zone too

Wow Glitchy

19:10 you can jump in before hitting Robotnik on Whitehead’s iOS version

By I have login glitch when I am logining the not logining please give solution

In sonic 3 I was able to pull of the the infinite invincibility music glitch accidentally

Sonic: well this is fine hehe... *sonic gets nightmares*

Ooh, that broke hard.

Maybe because 0-1=-1 but -1 in sonic 1 = 255 and 256-1=255

11.10 is the set up to the level wrap on marble 1 marble 2 and 3 have them as well with practice you can do marble 2 in 11 seconds.... Speedrun strats 😉

now do it with sonic 06. (18 hour video)

spike bug COULD be intentional, as the code for the spike hurting is entirely seperated from all the other spike hurting code. as for it being 'fixed', Sonic Team may have forgotten about that and instead replaced the code.

you can do the first glitch in sega genesis classics on all devices its supported on. even nintendo switch. all you need to do is disable the sprite limit

6:04 - the same in ending cene!!

The title screen sonic bug happens sometimes on genesis hardware sometimes

Im suprized i didnt see the slope glitch!

Damn your really funny i like it

3:50 the layer of sound thats missing is the DAC correct me if i am wrong

why does it try to read the illegal instruction?

sonic 1 is so fucking broken on release, im suprised sonic even became popular to all these bugs, glad overtime sega saw their mistakes, until shadow the hedgehog (2005)

28:38 This should be Gay Baby Jail too

Fun fact:in the glitch where you die from the bottom,if you try to do the same thing of mobile port at the start of act 1,the game crashes, k o o l

your vídeo is soo good, it feels like i'm watching a cybershell video somehow

14:20 now i can try to beat Labyrinth Zone Act 3 Boss without returniung in different runs

19:05 this glitch works on the remaster as well.

14:41 Tap/click Read more for full explanation The reason why Sonic can gain 255 lives is because of an integer underflow. So if the life counter is 1 (Internal value is 1-1=0) and you get Sonic to die twice, the Game Over check is skipped, as the game checks to see if the internal value is 0 or not, but that check happens _after the death animation is finished and the live counter has finished decrementing the internal life counter_ This bug also happens in Sonic 2 (MegaDrive/Genesis) Chemical Plant Zone. So 1-1-1=-1, but since the life counter is an 8-bit unsigned integer (positive numbers + 0), it will wrap around to 255, then decrement by 1, which means the internal value is 254. For Sonic getting a life increments it to 255, but making Sonic to get one more life resets the internal life counter _back to 0_ so that means if Sonic lose a life when his life counter is 0, all 256 tries are essentially wasted, as the game checks if the external life counter is 0 (internal is 255) or not when decrementing (incrementing does no effect) before setting the GameOver flag in the game after the death animation is played and the internal counter is completed the decrement process. It's the same thing with Pacman's Level 256 glitch. P.S. I'm speaking from decino's perspective.

1:59 fu##i wuggy

16:03 you can't fix something thats been damaged "friend."

He called green hill Emerald hill

Spike Bug is really annoying, they removed in Sonic 2. Music bugs must be fixed or it's unfixable Sonic 1 Labyrinth Zone glitches: Act 1: ??? Act 2: Clip & Illegal Istruction Act 3: ???

20:30 naw sonic is now sink (cannon)