Andrew Owen has made the first release candidate of the U3.5: Pax Britannia tileset available for download:

Here’s the first release candidate of the U3.5 tile set. It’s closest to the EGA U4 set, but with some U3 (healing station, thief, cleric and serpent), U4 Upgrade Patch (demon, devil and text) and U5 (walls, floors, doors and ladders) influences. The tiles have 8×1 attributes (only two colors per 8×1 pixel block).

There’s little more than needs be said. Click on through to grab the tileset for yourself!