https://www.gamespot.com/articles/save-20-on-ps4-pre-orders-for-these-games-in-the-u/1100-6458432/

As you may know, both Amazon and Best Buy have programs that offer 20% off video game pre-orders. Amazon's is called Amazon Prime, and Best Buy's is called Gamers Club Unlocked. But to participate in those programs, you have to pay money upfront. Thanks to a PlayStation Store promotion called Totally Digital, you can save 20% on select PS4 game pre-orders without spending any additional money at all. Six games are in the program, and the first two launch April 24.

The first two games to get 20% pre-order discounts are The Swords of Ditto and To Leave. The Swords of Ditto is a cartoonish co-op RPG that borrows more than a little from both Adventure Time and the top-down Legend of Zelda games--but it's not without ideas of its own. To Leave is a platformer about a manic depressive man who uses a magical flying door to navigate the environment. Let's just leave it at that.