Super Mario Bros. is one of the most well-known video games ever made, so you’d think it would be impossible for there to be new discoveries made about its development or its code. Never count out a speedrunner, though. In a recent video posted by prolific Mario speedrunner Kosmic, he discovered a way to access an entire series of glitched levels in Super Mario Bros. The Lost Levels, aka Super Mario Bros. 2 Japan. While “new” isn’t technically correct, no one has been able to claim they’ve beaten level B-L until now.
Kosmic breaks down how he came about these levels in pretty succinct detail, but I’ll provide a quick summary. The way the level/world counter in Super Mario Bros. 1 and Lost Levels works is by the object the player uses to finish a level. Grabbing the flagpole at the end of a course will increase the second digit on the counter, while grabbing an axe in a castle increases the first digit. This is why some ROM hacks will have levels like 1-6, etc.
It’s not as simple as that, however. If you’re familiar with the infamous “Minus World” in the original Super Mario Bros., players are able to access that by clipping through walls and taking pipes that shouldn’t be accessible yet. That has to do with page manipulation in the game’s code, but Kosmic explains it better than I could. Through a similar method, he does something similar in The Lost Levels and that resets the world he is currently on while retaining the level number. With this, he’s able to progress through World B beyond the castle and into B-5. After several loops, he winds up at B-M (the second digit proceeds into letters after hitting 9) before the game craps out.
It’s really fascinating stuff, but it’s especially intriguing because of the age of the game. No one has ever managed to do this before despite no outside modifications being needed. Kosmic doesn’t even utilize a Game Shark to make this happen. While the levels are technically not new — they start to recycle from the next world and so on — the way they are drawn on screen is… well, colorful is a way to put it.
If you’re a fan of old-school Super Mario Bros., the video is absolutely worth a watch. It’s amazing what kinds of things are hiding in games that are legally middle-aged.
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Written by Peter Glagowski
Peter has been a freelance gaming and film critic for over seven years. His passion for Nintendo is only matched by the size of his collection.
