This hack adds a number of bug fixes, improvements and other miscellaneous Tweaks to Super Mario Bros. This is done without any added mappers. Using asm6f or another assembler, one can choose which Tweaks to add or remove, depending on taste. This can be done by cloning the source from the GitHub repo (listed under Source Code in the Hack Information on the left) and following the build instructions there.

Modifications

• Victory theme B-section: Despite its original removal being that it did not fit in the cartridge, due to a lot of optimisations, it has been added in.
• Flagpole 1-UP: When the player touches the top of the flagpole, they will now earn a 1-UP.
• Modern scoring: If the player bounces on many enemies in a row, defeats many enemies using a star, or kicks a shell into a long enough row of enemies, they will get more points and eventually 1-UPs.
• Modern power-up scaling & damage scaling: Power-ups now work like they do in later games.
• Modern enemy bouncing: When the player holds A while bouncing on an enemy, they will now bounce higher, like in later entries.
• Modern enemy movement: When enemies land on the ground or touch the player, they will now continue to walk in their direction, like in later entries.
• Unconditional 1-Up blocks: 1-Up blocks now always spawn.
• Title music: Adds an alternate version of the Underwater theme to the title screen. Strictly speaking, this alternate version is an unintended side effect of a bug, but it does sound quite nice.
• Dynamic lives screen: The lives screen now changes depending on what state Mario or Luigi is in.
• Super Mario Bros. Deluxe Luigi palette
• Consistent shell speed: Shells now move the same speed in the air as on land. They can also go over 1-tile gaps now.
• Force pipe crouching: Super and Fire Mario/Luigi now always crouch when entering a pipe, as opposed to sometimes.
• Allow Player 2 pausing: In the original game, only Player 1 can pause the game, since the Famicom only gave Player 1 a start button. This Tweak makes it so that both players can pause.
• Remove hammer bounce: Hammers now travel along their arcs when they hit the player. They are only bounced back when the player is invincible.
• Green underwater Cheep Cheeps

Fixes

• Fix World -1: The scroll locking now works as intended. Doing the glitch anyway brings a surprise.
• Fix lives: Lives are now capped at 99, and displayed properly.
• Fix Spiny velocity: Lakitu now throws his Spinies with the velocity the designers intended.
• Fix crouching: Crouching is improved, removing some glitches like the infamous “getting stuck in the water levels” glitch.
• Fix powerup momentum: When the player collects a power-up while jumping, they will keep their vertical speed now. This sadly also removes the power up jump glitch.
• Fix star flagpole glitch: When the player is invincible while touching the flagpole, they’ll now lose your invincibility, rather than having the music glitch out.
• Fix starting input: When the player holds A or B while entering a level or exiting a warp pipe, the player will no longer jump or fire a fireball. This removes the skating glitch as well.
• Fix 5-1 small castle: Turn the small castle at the start of level 5-1 into a big castle, like it should be.
• Fix Spiny block defeating: When the player bumps a block with a Spiny on it, the Spiny will now be defeated.
• Fix the star power-up jumping out of the block: When a star comes out of a block, it will now always jump out, instead of sometimes falling out.
• Fix small Mario’s reversed walk cycle: Small Mario now doesn’t moonwalk anymore.
• Fix the collision of invisible blocks.

Changes from the PAL (European) version of the game

• Optimise Cheep Cheeps: Takes the Cheep Cheep code, and makes it a whole lot shorter and faster.
• Fix spring spawning: Makes it so that the spring spawning function doesn’t override important sprite slots, leading to fewer glitches.
• Fix spring force.

• Database match: Super Mario Bros. (World)
• Database: No-Intro: Nintendo Entertainment System (v. 20210216-231042)
• File SHA-1: EA343F4E445A9050D4B4FBAC2C77D0693B1D0922
• File CRC32: 3337EC46
• ROM SHA-1: FACEE9C577A5262DBE33AC4930BB0B58C8C037F7
• ROM CRC32: D445F698