Microsoft on Tuesday eliminated the charge for a series of downloadable maps for its smash hit Halo 3 video game. The add-on maps let online players add new battle zones to the Xbox 360 title.

The three maps in the Halo 3 Heroic Map Pack are now available for free through the Xbox Live marketplace. The maps previously cost 800 "Microsoft points", or about $10.00.

One map, called "Standoff," features a symmetrical valley with entrenched bases and boulders for cover. Another, titled "Rat's Nest", provides players with "labyrinthine passages" to work through, according to Microsoft. Finally, "Foundry" includes numerous, editable objects -- such as walls, bridges, and tunnels -- that players can place wherever they like to create a custom battlefield.

Microsoft also said it would release a new series of maps on April 15 in a suite called the Legendary Map Pack. The pack will cost 800 Microsoft points.

A first person shooter, Halo 3 features a biologically enhanced super-soldier named Master Chief who -- armed with plasma rays and other futuristic weapons -- has to blast his way through various levels to accomplish missions. He's countered by an alliance of hostile aliens called The Covenant.

Since it Halo 3, Halo 3 has set numerous video game industry sales records. It posted $170 million in first day receipts, and took in $300 million in its first week. To date, more than 5 million copies of Halo 3 have been sold.

Master Chief was ensconced in popular culture when Madame Tussauds' wax museum in Las Vegas in September unveiled a "life size" statue of the character standing 7-feet, 2-inches tall.