6 reasons why you should play online Half-Life shooter Sven Co-op right now

Fast and furious Half-Life mod Sven Co-op has turned into a free standalone game on Steam 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.

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For better or worse, Sven Co-op is organized chaos. Landing in the middle of a 32-player server mid-campaign is like abseiling into the electronics section of a high-street retailer on Black Friday. Being swept along with the crowd is all part of the fun; until, that is, somebody decides to block off the exit to an underwater section and causes the whole team to drown. Thanks, U_MAD_BRO123.

Well, duh. 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. Soldiers discuss tactics in distorted union on their radios, three-legged Gonarchs are as terrifying as ever, and unleashing a family of snarks upon an unsuspecting enemy while crouched in a vent is still one of the most satisfying ways to add to your kill tally.

"Hey everyone, is there mushroom for one more player? I'm a funghi..."

Sven Co-op has been around for a long time in mod form, meaning there are more than 900 community-made maps to play through. Maps have different difficulty levels, feature different horde sizes and pit you against bosses of varying toughness. The way that most maps are designed means you're unlikely to make it through to the end unless you cut through the chaos to help your team-mates.

Some maps equip you with a full set of weaponry from the start, while others force you to cope with a crowbar and a medkit until you stumble across an armoury. Some of the most popular maps are 'Crystal', 'The Escape Series' and 'Osprey', but whichever you land in, it's unlikely to feel the same as the previous one.

They might be more scripted than an episode of the X-Factor, but Sven Co-op's turret set-pieces are as satisfying as ever. As vortigaunts spawn left, right and centre, ask a team-mate to stand by and heal you while you rain a hail of bullets upon the enemy like a minigun-wielding T100. You won't run out of ammo either, meaning you can spray and pray to your heart's content until it's safe to progress.

Well, probably – Sven Co-op's minimum specs wouldn't scare a calculator. The game's creators recommend Windows 7, a 2GHz dual-core processor, 2GB of RAM and a 128MB video card for the optimal experience. Looks like that decision not to upgrade your Pentium 4 rig was a savvy one after all.