https://www.pcgamer.com/tyranny-is-free-today-for-twitch-prime-subscribers/

Tyranny, the isometric RPG about being bad that's actually very good, is the latest addition to the lineup of free games being offered to Twitch Prime members. But you've only got until tomorrow to pick it up. 

Twitch Prime provides ad-free viewing, exclusive emotes and a chat badge, free channel subscription, and—as of March—free games every month. It's included with subscriptions to Amazon Prime, which offers free delivery on a huge range of products, access to Prime Video and Prime Music, and free ebooks via Prime Reading. Subscriptions recently went up from $100 to $120 a month (or $13 per month if you don't want to commit to a full year, but that'll end up costing you more in the long run), but it's still a pretty sweet deal if you're a regular Amazon user.