Koopalings, also known as the Koopa Kids, are Bowser's seven children (it is unknown who their mother is). They first appeared in Super Mario Bros. 3, with each one serving as the boss at the end of the first seven worlds. They also serve as world bosses in Super Mario World (except for Larry, who shares Valley of Bowser with his father). Their names are Iggy Koopa, Morton Koopa Jr., Lemmy Koopa, Ludwig von Koopa, Roy Koopa, Wendy O. Koopa, and Larry Koopa, listed in order of appearance.
Because of the Mode 7 effects used in most of Super Mario World's boss battles, Lunar Magic cannot normally render the levels that the Koopalings appear in. This means that they are for the most part unmodifable. Lemmy and Wendy are the exceptions; they are normal sprites and can even be used in normal levels. However, great care must be taken to prevent Yoshi from entering these levels, as Yoshi can eat the decoys (and even the Koopa Kids themselves), which will cause both the decoys and the Koopaling to stop appearing and make the level unbeatable. Note, however, that it is okay to bring a shell into these levels; it will simply kill the decoys who will pop up again with the real Wendy/Lemmy, who is immune to the shell.
It is possible to add additional sprites to the other battles by temporarily changing the level mode in the "Change Properties in Header" dialogue box. Typically, Bullet Bill generators are added to up the challenge, but this can result in graphical glitches.
The Koopalings' graphics in Super Mario World look quite a bit different from their official artwork, and giving them a more classic look requires the aid of a hex editor.
Morton, Roy, and Ludwig's palettes can be changed from green, blue, and yellow into a more traditional grey, pink, and blue. This is accomplished by changing the values at address 0x1DF6E to [84 CC A4] and the values at address 0x1DF73 to [B3 B3 B2]. To give them the colors they had in the ending of the game, change the values at address 0x1DF6E to [78 84 CC] and the values at address 0x1DF73 to [B3 B3 B3].
Lemmy's palette can be changed from yellow to green. In the range of addresses 1D42E-1D49C, the lower digit of each byte that ends change in 5 must be changed to B, while leaving the higher one as it was. To make Wendy use a pink palette instead of the red one, in the range of addresses 1D4B8-1D526, each byte with a low digit of 9 must be replaced with F.
There is also an issue where Wendy's bow's graphics are jumbled in an animation where she looks side to side. To fix this, replace the strings at these addresses with the following:
- 0x1D1AF: 08
- 0x1D1B5: 08
- 0x1D3D7: 1F 1E
- 0x1D3DD: 1E 1F