Where to Find Free Downloadable PC Games Legally: 100% Legitimate Sources

I can't link piracy sites. Here are 100% legal sources for free PC games:

Free-to-Play (F2P) – Major Launchers

• Steam → Free to Play filter: Dota 2, CS2, TF2, Warframe, Path of Exile, Destiny 2, Apex Legends, Lost Ark
• Epic Games Store – Free weekly game (permanent keep) + F2P: Fortnite, Rocket League, Fall Guys
• GOG.com – "Free Games" shelf: classics (Beneath a Steel Sky, Ultima IV) + modern F2P
• Battle.net – Hearthstone, Heroes of the Storm, WoW Starter
• Ubisoft Connect – XDefiant, The Crew 2 (free weekends), Trackmania

Giveaway / Limited-Time Free

• Epic Games Store – Every Thursday 11 AM ET: new free game (keep forever)
• Prime Gaming (Amazon Prime) – Monthly free games + in-game loot
• Steam Free Weekends – Play full game Fri–Mon, then decide to buy
• Humble Bundle – Newsletter → occasional free keys
• IndieGala / itch.io – "Free" tag, pay-what-you-want bundles

Open Source / Public Domain

• itch.io – Thousands of free indie/experimental
• SourceForge / GitHub – Open-source clones (OpenRA, OpenTTD, OpenMW, 0 A.D., Battle for Wesnoth, SuperTuxKart)
• Internet Archive – MS-DOS / Win9x games playable in browser (legal abandonware)

Subscription Libraries (Free Trial)

• Xbox Game Pass PC – $1 first month (hundreds of games)
• EA Play / Ubisoft+ – Trials available

Bookmark IsThereAnyDeal + GG.deals for price tracking.