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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123 Strip Poker
card game / strip poker
LimeSoda

1Quest
RPG / roguelike
RatzNGodz

247 Mahjong
puzzle / mahjong
Games LLC

8-Bit Bayonetta
action / run and gun
PlatinumGames

Adventure Quest Worlds
RPG / MMORPG
Artix Entertainment

Anno Online
strategy / MMORTS
Ubisoft Blue Byte

atWar
strategy
atWar team

Batheo
strategy / MMORTS
Clap Along

Battlestar Galactica Online
shooter / MMOFPS
Bigpoint Games

Beijing Hidden Objects
puzzle / hidden object
Zygomatic

Bejeweled REMAKE
puzzle / tile-matching
szewczyk

Big Bang Empire
RPG
Playata GmbH

Bit Heroes
RPG / MMORPG
Juppiomenz

Bloxorz
puzzle
DX Interactive

Booty Calls
adventure / tile-matching
3X Entertainment Limited

Card Hunter
strategy / board game
Blue Manchu

Circus Hidden Objects
puzzle / hidden object
Zygomatic

Clicker Heroes
action / idle clicker
Playsaurus

Cut the Rope Time Travel
puzzle
ZeptoLab

Cyberpunk Dreams
RPG
Late Night Games

Daily Crossword
puzzle
zygomatic