Instructions
Start "Halo: Reach" and open the "Forge" subsection from the main menu. Select "Game Type."
Open "Race" and select either "Race" to create a linear or looping racetrack or "Rally" to create an overland racetrack with random checkpoints. If you have previously created a custom racing gametype you wish to use instead, you may select it here. While Forge works without selecting a gametype, this framework makes it much easier to tailor a race map without changing the basic mode type.
Open the "Map" menu and select the default map to edit. While any map will operate with racing gametypes, the "Forge World" map provides the most custom landscape options and the largest editing area and is a good base for any racetrack. Wait for the map to load and select "Start Game."
Press up on the directional pad to enter editing mode. Press "X" to open the object window and choose new objects and objectives to place on the map.
Use the "Gadgets," "Scenery" and "Structures" menus to build the physical track and obstacles. Do not use your entire memory budget, as you will need additional memory to place the race property items.
Open the "Spawning" menu and place an "Initial Spawn" item at the point you wish the race to begin. Press "X" and open the item's "Advanced" menu. Set the Game Type Label property to "Race_Spawn." This will spawn all players on a vehicle near this point. If you want to create different starting points for different teams, place multiple spawn points and set their "Team" properties as desired.
Open the "Objectives" menu and place several "Hill Marker" objects around that map to serve as race checkpoints. Press "X" over each marker and set their Shape property to "None."
Open the "Advanced" menu for each marker. Set the Game Type Label value to "Race_Flag." Set the "Spawn Sequence" value according to the order you wish the checkpoints to appear. Ensure the "Place at Start" and "Game-Specific" properties are both set to "True."
Press "Start" and select "Save as New Map" to save the racetrack to the hard drive. Select it from the Custom Game menu to play a match on the map. Make sure you use the corresponding "Race" or "Rally" gametype or the map will not function properly.