Metro 2033 free on Steam
from 11. March 2021 6 pm UTC 'til 15. March 2021 5 pm UTC
Steam currently offers Metro 2033 for free. Steam reviews are "Very Positive" (92% thumbs up).
The developers describe their game as following:
Set in the shattered subway of a post apocalyptic Moscow, Metro 2033 is a story of intensive underground survival where the fate of mankind rests in your hands.
You can watch the trailer here...
... and grab your free copy here: https://store.steampowered.com/app/43110/Metro_2033/
