Shadow Tactics: Blades of the Shogun is FREE to claim on GOG for the next 48 hours

https://www.gog.com/

The claim button is on the front page of the site. It's free to claim for the next two days. And apparently GOG is planning to do three more giveaways during their Winter Sale.

https://www.gog.com/news/hear_the_wind_howling_bringing_forth_the_gog_winter_sale_with_amazing_deals

"It’s gifting season, so expect a few nicely wrapped & merry presents from GOG! Shadow Tactics: Blades of the Shogun will be waiting for you as a gift until the 15th at 2 PM UTC. And three more giveaways will be coming your way to cheer up your days, so make sure to keep checking our hub and the calendar!"

EDIT: It looks like the other giveaways will happen on 12/16, 12/23, 12/27 and 1/3. Thanks to darthHottabich for providing the link to this:

https://www.gog.com/winter_sale_2021