You'll also find heavy discounts on Battletech (one of the best PC games of 2018), The Division, Shadow of the Tomb Raider and Stellaris if you browse through the Green Man Gaming sale. Battletech is 51% off, level with its lowest-ever price, while Shadow of the Tomb Raider is 57% off, another all-time low. Stellaris is a hair over $8/£7.
The Division is a whopping 86% off, making it just $7/£6. That's a steal, and now is a good time to play given that The Division 2 is out in less than two months.
It's worth poking around the entire sale, while the Humble Store is also offering decent discounts, which you can browse here.