GOG.com announces the launch of their Summer Sale 2016, a two week event that will conclude right before the beginning of the actual summer of 2016. They are offering deals up to 90% off, or 100% off if you count the fact that System Shock 2 is free for the first 48 hours of the sale, and there will be opportunities to earn other free games along the way. Here's word:

It's time for another adventurous Summer Sale! Join us for two whole weeks and lie by an ocean of game premieres and 1000+ deals, gather XP to unlock free games, and participate in summer activities! It's seriously the neatest one yet.

System Shock 2 is free for the first 48 hours to help us improve the GOG Galaxy client with a stress test giveaway. If you want to help out (and score a freebie), simply download GOG Galaxy, visit your experience page through the client, then claim and download your free game.

We'll have more and more deals for you every 24 hours as the 2016 Summer Sale marches on – and the deals will stick around until the end — starting with The Witcher 3: Wild Hunt (-50%), Rebel Galaxy (-50%), and Day of the Tentacle Remastered (-33%) as well as bundles including X-Wing and TIE Fighter, D&D Gold Box classics and more. Come, or stay, but do look out for more awesome deals and game premieres!

Collect XP to earn free games
This is the really cool part – check in every day, participate in activities to collect badges, and buy stuff during the sale to earn XP. As you progress, so will your Summer Sale hero, plus you'll unlock free games: Spelunky, Gabriel Knight: Sins of the Fathers – 20th Anniversary Edition, and Dreamfall Chapters Season Pass.

GOG Plays on Twitch.tv/GOGcom
Join us for the grand Twitch plays event and help achieve greatness in Stardew Valley and Grim Fandango Remastered. For every challenge we complete everyone will get an extra XP boost. The first, Stardew Valley, event begins Thursday, June 9, at 4:00 PM UTC – where you will be tasked with the greatest feat of all: to plant a Parsnip. It's going to be all kinds of ridiculous.

We'll be streaming great games all sale long too, so check out the schedule and tune in!