Games like Starsiege: Deadzone

If you finished Starsiege: Deadzone, the closest matches are Warhammer 40,000: Speed Freeks, Tom Clancy's Splinter Cell: Conviction, Metal Gear Solid: Portable Ops, Sniper Ghost Warrior Contracts 2 and Firewall Ultra. All 9 share its shooter genre and are ranked by how closely their themes and modes overlap.