Fast and furious Half-Life mod Sven Co-op has turned into a free standalone game on after 17 years, so you really have no excuse not to give it a go. Featuring levels packed with hivehand-armed alien grunts, electricity-slinging vortigaunts and the same soldiers that gave your quicksave finger plenty of exercise back in 1998, Sven Co-op is a nostalgic trip back into Gordon Freeman's world. Here are six reasons why you should download it, pronto. • Prev Page 1 of 7 Next Prev Page 1 of 7 Next 1. Nobody really knows what they're doing. Sven Co-op is set in Half Life's original game world, so prepare to feel nostalgic if you played Valve's classic and its Opposing Force/Blue Shift spin-offs all those years ago.