End of Nations will undergo many enhancements and a lot of fine-tuning before release, but even in its current state, the game is unquestionably impressive. Specifically, the scale of the action is simply astonishing. The demo map I saw spanned many (virtual) square miles, featuring an array of locations and topography. One second I was seeing a skirmish in a burning forest, and in the next, several players were working together to bring down a massive Panzer Hulk (think: battleship with tank treads) at a heavily fortified construction facility.
All players will have a "secret headquarters" in the game world, from which they can select the units for their armies and deploy them at any time. These bases could almost be looked at as representations of each player's commander character rank; as bases' maximum sizes increase as players level up, allowing for the placement of more facilities to aid in battle. One addition I saw was an airstrip. Once it was built, forces in the field could call in bombing runs on their opponents.
The demo itself was a brief, high-level introduction to the game, but Petroglyph is promising some cool features for the finished game. One of the most promising is a drop-in-and-drop-out co-op system. Using a 3D globe, players are able to see where and how intense the fighting is in the game world at any time, including where their friends happen to be engaged in combat. From there, entry into the game is intended to be as simple as clicking a spot on the map and choosing which of your units will be air-lifted into battle. You'll also be able to leave a battle at any time, and it will keep on going.
End of Nations is ambitious, and while it may be one of the first games published by Trion Worlds, its developer has a proven track record in the genre. What I saw showed a lot of promise, and I'm eager to actually play it at E3 in June.