In a nutshell: Looking for a freebie? There are two offers available right now that look pretty compelling: while not an entire game, the Dubai mission from the excellent Hitman 3 is temporarily part of the new Hitman 3: Free Starter Pack. And retro fans can grab the original---i.e., not the terrible remake---classic cel-shaded shooter XIII.
The demo of the critically acclaimed Hitman 3 is now available on the Epic Games Store. It includes full access to two locations---the ICA Facility and Hawke's Bay---the two tutorial-style prologue missions from Hitman (2016) and Hitman 2 (2016), respectively.
Additionally, the Free Starter Pack will "periodically" add other locations, the first of these, available this week, is Dubai. The massive level takes place on top of the world's tallest building and is considered one of the game's best missions.
Elsewhere, GOG is giving away XIII. Don't worry, though; this isn't the notoriously bad remake from last year that was so broken, the devs were forced to apologize (blaming the pandemic). It's the much-loved original from 2003. GOG users have rated it a respectable 4.2/5, so it's definitely worth a look. Better hurry: the offer expires in around 26 hours.
GOG is also running its spring sale right now. Some of the best offers include 75% off Mad Max ($4.99), 92% off XCOM 2 ($4.79), 60% off Pillars of Eternity II: Deadfire - Obsidian Edition ($23.99), and 20% off Disco Elysium - The Final Cut ($31.99).