If using the crappy Epic Games client isn't an obstacle to true love (or at least scoring free shit), the Epic Games Store will be offering up a freebie every two weeks or so.
Subnautica is the first cab off the rank, and will be up until Friday (at which point it'll be replaced by Super Meat Boy, which you probably already have six copies of from various bundles you bought absent-mindedly a full console generation ago).