Brothers: A Tale of Two Sons will be free to download for North American PlayStation Plus subscribers from Tuesday, Sony has announced.
Worms: Battle Islands for PSP and Vita will also be a free download following Tuesday's PS Store update, while Sony is offering a selection of discounts on music games.
Irrational Games' BioShock Infinite joined the US Instant Game Collection last week.
CVG's Brothers: A Tale of Two Sons review was full of praise for Starbreeze's game, concluding: "Short, simple but immensely satisfying, it's Ico meets Limbo in Fable's world. One word: spellbinding."
PS4 owners are required to subscribe to PS Plus in order to play online multiplayer, which isn't the case on PS3 or Vita.
The thinking behind the decision to charge customers for online multiplayer on PS4 was explained to us by Sony Worldwide Studios president Shuhei Yoshida in June.