343 Industries is working with modders to make Halo 2's long-lost E3 exclusive level, Earth City, playable.

Cast your mind back all the way to 2003 - if you're old enough to think that far back, chances are that you'll remember Halo 2's gameplay debut, which showed a level called "Earth City". The gameplay demo made a massive impact for its advanced lighting techniques and because it finally took the series away from the Halo ring.

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The level shown in that E3 demo was never made playable in the final game, but 343 Industries has revealed that it will be making the level playable in Halo 2's retail build for the first time as part of a secret "Digsite" project that aims to collate cut content and restore unfinished assets to the game.

Within a massive blog post detailing the secret project, 343 Industries community writer Alex Wakeford blah said, "We've teased this in a few of the shots above, but I can confirm we are working on a rebuild of the original E3 Earthcity scenario that makes it playable in modern retail Halo 2."

Wakeford continued, "This was NOT a trivial process, and we should probably layer on a whole page of caveats that come with taking a demo map for an engine that no longer exists and getting it to not blow up the current lightmapper (among other issues that come from letting people go into areas that were never intended to be seen)."

Although Earth City is the major highlight of the Digsite project for most Halo fans, it's not the only cut Halo 2 level that's being restored. Wakeford also revealed that Alphamoon, a level that was reworked into some of the gas mine levels in the final game, is being reworked to be fully playable.

Wakeford said, "Portions of this map got worked into the gas mine levels (such as the boss fight against Sesa ‘Refumee, the Heretic leader), but people have never had the chance to experience this level as intended. Campaign maps require several orders of magnitude more work than a multiplayer map, so being able to get this restored is a source of real pride!"

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