Browser based free games
Play free and free-to-play games designed to be played direclty in a browser (this includes both browser-based games and flash games)
Here are some of the best browser games you can play directly online: MMORPGs, collectible card games, strategy games and more. Browser games usually doesn't require nothing more than an updated browser (Chrome, Firefox, Edge, Opera, etc.) and are playable on any PC or Mac. Some of them may require a Flash plugin.
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Tentlan
strategy / MMORTS
Lionmoon

Epic Battle Fantasy 3
RPG / JRPG
Matt Roszak

247 Mahjong
puzzle / mahjong
Games LLC

8-Bit Bayonetta
action / run and gun
PlatinumGames

Popmundo
simulation
ExtraLives AB

atWar
strategy
atWar team

The Settlers Online
strategy / MMORTS
Blue Byte Software

Star Wars Combine
RPG / MMORPG
SWC Programming Team

Travian: Legends
strategy / MMORTS
Travian Games

Strip the Difference
puzzle
Gang of Gamers

Imperia Online
strategy / MMORTS
Imperia Online Ltd.

Therian Saga
RPG
Fatecraft

Progress Quest
RPG / idle clicker
Eric Fredricksen

1Quest
RPG / roguelike
RatzNGodz

The Monster Inside
adventure / visual novel
Random Seed Games

Fairune
RPG / JRPG
Skipmore

Empire Universe 3
strategy / MMORTS
Looki Publishing

RPG MO
RPG / MMORPG
Marxnet

Initium
RPG / MMORPG
Universe Projects Inc

Batheo
strategy / MMORTS
Clap Along

Hero Zero
RPG
Playata GmbH