That's not what I'm posting to talk about, however. To do colored backgrounds like Giga Drain, insert the following:
02 24 7B 3E 08 02 05 01 00 SS 00 00 00 YY 00 XX XX 05
Where XX XX is the color you want, YY is the intensity (0C for Giga Drain- 10 replaces the background entirely with the given color), and SS is the speed of the transition (01 for Giga Drain, but I imagine Hyper Beam and other attacks use the same logic with a higher value). To revert the background to normal, place the following:
02 24 7B 3E 08 02 05 01 00 SS 00 YY 00 00 00 XX XX 05 0B 03 0D
The values here do not have to be the same, but I'd advise making the color and intensity the same or it will abruptly change at the start of the transition back.
This allows us to accomplish animations that benefit from backgrounds without always having to insert new ones, like so: