Here’s the U3.5 beta tileset. Quite similar to the EGA U4 set, but with some U3 (thief and cleric) and U5 (walls, floors, and doors) influences. One thing to remember is that the tiles have 8×1 attributes (only two colors per 8×1 pixel block). The target machine can’t do per-pixel color anyway, but on the plus side this format means the tiles only take up 16K of RAM.