https://mailchi.mp/841f564080b9/nggnewslettergiveaway -sign up for their newsletter on that page to get a Free copy of Pirates: All Aboard today only. Once you own that game(or any No Gravity game), you’ll qualify to get a Free game every day until December 20.
The free games will be listed daily at this link starting on Monday, December 11, but you have to do it every day or you won’t qualify for the future free games. The free pirates games doesn’t seem to come immediately, so hopefully they send the code before the promotion starts on Monday.

https://www.nintendo.com/store/products/just-dance-switch/ -Nintendo Switch owners can get a Free Just Dance Game Download in the Nintendo Store.

https://store.epicgames.com/en-US/p/adios-b378b4 -click the get button to get a Free Adios PC Game Download from Epic Games.
https://store.epicgames.com/en-US/p/hell-is-others-789262 -click the get button to get a Free Hell is Others PC Game Download from Epic Games.

https://store.epicgames.com/en-US/p/thems-fightin-herds -click the get button to get a Free Them’s Fightin’ Herds PC Game Download from Epic Games for the next 24 hours.

https://store.steampowered.com/app/1222670/The_Sims_4/
https://www.xbox.com/en-US/games/store/the-sims-4/c08jxnk0vg5l?
https://store.playstation.com/en-us/product/UP0006-CUSA09209_00-THESIMS400000000/ -get a Free The Sims 4 PC, Xbox, and Playstation Game Download.

https://store.epicgames.com/en-US/p/geneforge-1-mutagen – click the get button to get a Free Geneforge 1: Mutagen PC Game Download.
https://store.epicgames.com/en-US/p/hood-outlaws-and-legends – click the get button to get a Free Hood: Outlaws & Legends PC Game Download from Epic Games.
https://store.epicgames.com/en-US/p/iratus-d0e5ba – click the get button to get a Free Iratus: Lord of the Dead PC Game Download from Epic Games.

https://store.epicgames.com/en-US/p/insurmountable-b02c31 -click the get button to get a Free Insurmountable PC Game from Epic Games.
https://store.epicgames.com/en-US/p/xcom-2 -click the get button to get a Free XCOM 2 PC Game from Epic Games.

https://www.epicgames.com/store/en-US/p/pc-building-simulator -click the get button to get a Free PC Building Simulator PC Game from Epic Games.

https://www.noggin.com/noggincares/?step=sign-up -fill out the form and activate by email to get a Free 1-Year Noggin by Nick Jr. Subscription. Payment information is not required. It will end after a year.