Th Amiga was designed by Jay Miner, creator of the original Atari 8-bit line. Raster interrupts allowed the computer to change colour palette as the scan line moved down the image: giving more colours on screen as the hardware would normally allow. Here’s a screenshot from an old post of mine:

That’s very cool! Good to know the technical reasons why.

the SNES could also do this! in fact, the same hardware feature was used to do effects like the keyholes in Super Mario World and the X-Ray Scope in Super Metroid it's also how the pseudo-3D perspective effects in Super Mario Kart were accomplished