New feature: Invite a Friend

- Invite a friend into your game and play Aloof together online!
- You and your friend can freely move around between any game mode, like:
- Co-op Campaign
- Player versus Player
- Offline Adventure (versus AI)

Other changes to: Player versus Player

- Now has 23 levels!
- Levels are divided into easy, medium and hard
- Let the computer select a _random_ easy, medium, hard or just any level