Mode 0

What is Mode 0?

Mode 0 is the first mode on the SNES, characterized by its offer of four layers, as opposed to the normal three Mode 1 offers you. However, there are two significant drawbacks: you only have four colors (3 actual colors plus transparency) per palette, and the layer 3 tilemap is halved to make room for layer 4. However, the latter drawback can be circumvented by sacrificing GFX slots.

Applications of Mode 0

When it comes to the SNES library of games, only a few have used Layer 4, such as Super Mario Kart, Super Mario World 2 - Yoshi's Island, S.O.S., and Earthbound.

To make things more interesting, in the field of Super Mario World hacking, a few hacks and contest levels have used it, such as ASMWCP, LMPuny's work-in-progress SUPER MARIO BROS. Returns, idol and Katrina's Chocolate Level Design Contest 2018 entry lightest, and AnasMario130's Power Mario Contest entry Pyro-Blue's Fort.

Palette and Tilemap Distribution

As mentioned in the previous heading, Mode 0 can only offer you four colors per palette, including transparency. Each layer takes up 8 four-color palettes distributed in two rows each. Layer 1 takes up rows 0-1, layer 2 rows 2-3, layer 3 rows 4-5, and layer 4 rows 6-7.

As for the tilemap, it is 2bpp, but the size must be 4 KB. However, the arrangement for the tilemap is doubled, meaning that in a graphics editor like YY-Chr, you can have eight rows' worth of graphics instead of the usual four.