A game called Jotun: Valhalla Edition is free to own forever.
As long as you claim your copy before 19th May, 15:00 UTC / 16:00 BST.
Jotun is a hand-drawn action-exploration game set in Norse mythology. In Jotun, you play Thora, a Viking warrior who died an inglorious death and must prove herself to the Gods to enter Valhalla.
This game has been given free before. You may already have it if you follow this forum section regularly.