Kirby Super Star has several different ROM versions.

The initial version (1.0) of Kirby Super Star is the base game, and is only limited to Japanese.
The final version (1.2) has minor bug fixes that do not alter much of the gameplay. This version of the game appears in all languages, Japanese included. In addition, all future official releases of the game (ex. Virtual Console and Nintendo Switch Online) use version 1.2.
A 1.1 version exists, but it is believed to be the same as 1.0. More research on this version is required.

Identifying Cartridge Version

 
General location of where the imprint should be.

It is possible to identify Japanese cartridge versions by looking at the back label of the cartridge. Most, if not all, SNES/SFC games will have a small imprint on the back label of the cartridge. This label can be used to determine cartridge versions.

To-do: Confirm all three of these labels with a cartridge dumper, especially 1.1.

1.2 Patches

These bug fixes are the current ones that are known to exist.

Simultaneous D-Pad Inputs

In version 1.0, pressing Up and Down / Left and Right at the same time will cause unexpected behavior in certain spots in the game (mostly crashes or visual bugs).
Some examples are pressing Up and Down on a ladder, or pressing UD / LR in Nova.
If the game crashes from this glitch, the game’s save data is overwritten with junk data, which consequently deletes all save data.
In version 1.2, this bug was fixed by no longer accepting both inputs at the same time.
(In 1.2, the only crash bug that exists as of now is the Nova Sleep bug)

Blade Knight Helper Beam

In version 1.0, Blade Knight cannot shoot sword beams under normal circumstances due to an oversight programming the HP required for a sword beam.
At max HP, Blade Knight will be at 48 HP, which is different from Kirby’s max 70 HP.
(If modified, Blade Knight will shoot a beam if the HP is set to 70).
Therefore, the game believes that Blade Knight is not at full HP, so you can never shoot a sword beam.
This bug was fixed in version 1.2, but consequently allows Kirby to shoot a sword beam at 48 HP, despite not being Kirby’s max HP. This means that regardless of the version, the sword beam is always incorrect.

Dark Knight Translation Error

In the Japanese version, the name of Dark Knight that appears in the second Battle Windows boss fight appears as “DARK NIGHT” in version 1.0, but was corrected to “DARK KNIGHT” in later versions.
This boss is shown as “EVIL KNIGHT” in the English version.

Air Swallow

If Kirby inhales something other than recovery items, and takes damage at the same time, Kirby will swallow nothing the next time he inhales. This is only possible on version 1.0.

Mirror Death

If you die in Revenge of Meta Knight due to a time-out while using the Mirror Body move, Kirby will die, but his helper will remain. This does not happen in version 1.2.

Soul Bracelet Tile Fix

A single tile was fixed in the room containing the Soul Bracelet treasure to be filled instead of empty. (provide images circling the tile)

Damage While Hovering Underwater

In version 1.0, if Kirby takes damage underwater while in a floating state, he will stay in the floating state.
In version 1.2, Kirby will stop floating underwater if he takes damage.

Region Differences

Game Title

NTSC-J: 星のカービィ スーパーデラックス (Hoshi no Kābī Sūpā Derakkusu, Kirby of the Stars Super Deluxe, commonly abbreviated as SDX or スパデラ Supadera)
NTSC-U: Kirby Super Star (commonly abbreviated as KSS)
PAL: Kirby’s Fun Pak

(Going forward, the “English” version will refer to both Kirby Super Star and Kirby’s Fun Pak)

Text

The Japanese version takes less time to scroll text, which saves time in speedruns.

  • Both English and Japanese load characters at the same speed and have the same amount of text boxes; differences between the languages such as Japanese's usage of fixed-width characters, wider than most characters in the English version of the game, mean that there are generally fewer characters in a Japanese text box than in its English equivalent.

Text scrolling only appears in Revenge of Meta Knight cutscenes and Battle Windows (which appears in Great Cave Offensive, Milky Way Wishes, and The Arena)
The Japanese version saves roughly 25 seconds over the English version due to text scrolling.
The calligraphy writing at the end of Samurai Kirby, as well as on Chef Kawasaki, remain in the English version.
Some English text appears in the Japanese version, such as in the title screen of Dyna Blade. However, this is typical in media if loan words are used.

Food Items

Some food items were changed between versions. A detailed list can be found here. (To-do: add this list to the wiki)

Tutorial Prompt Background

In the Japanese version, the beginner mark (Wakaba mark) is used in the background of the tutorial prompt before certain subgames.
This image was changed to Kirby in the English version, as it isn’t a recognized symbol in other areas of the world.

Controller Graphics

Depending on the game version, the controller graphic during the tutorial sequence will have different colored A B X Y buttons to match with the controller of that region.

In the PAL version of the game, the tutorial refers to the controller as having purple buttons, despite PAL controllers not having those colors.

Miscellaneous Changes

Title Screen Waiting Time

In the Japanese version, the file select screen can be accessed immediately by pressing a button the moment the title screen is shown (by holding an input before it is shown, a button press can be buffered to skip the cutscene immediately). In the English version, it is required to wait a moment before pressing a button to advance to the file select screen, which makes the button buffer impossible. Consequently, the English version is less consistent with RNG manipulation, as the title screen cannot be skipped at a consistent time.

Off-Screen Wham Bam Rock Hitbox

If Wham Bam’s hand is not present, an off-screen hitbox to the right can be hit in the Japanese version. The English version does not have this bug.