Jodrell Bank is an optimized Team Slayer course that Bungie says will allow for a greater number of players "without overcrowding things."

Purple Reign is described as a "gently sloping bowl" with "wider lines of sight for players staring down one half of the map and an intricate and strategic mix of floor/column/ramp gameplay on the other side," good for sneaky jumps.

Vandelay "is structurally the simplest map we've ever made," says Bungie, "yet the tools that we're providing with the help of the Forge give the map tons of potential."

All three maps are expected to be released as the first Halo 3 map pack. Dates and prices have yet to be revealed.

The "Halo 3 Heroic Map Pack", 800 points, is now available.