mode 7 background

the level editor does not change the lower half of the screen. i copied every color palette from the world of ruin to match with the world of balance and i still get the world of balance horizon line with the world of ruin sky.

You can change everything in this game with the documentation available and the amount of time spent of disassembling this game. If what Gi Nattak say doesn't work or the level editor doesn't allow you to to do it, then there must be a way to do it with ASM, though I don't have the time to look for an answer. You should start learning how to read and modify code for any medium hacking difficulty task, e.g. everything that can't be done with the editor we have. Angelo gave you the place to look for.