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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Batheo
strategy / MMORTS
Clap Along

Hero Zero
RPG
Playata GmbH

Circus Hidden Objects
puzzle / hidden object
Zygomatic

Strip Blackjack 3310
card game / strip poker
GGBot

Drakor
RPG / MMORPG
Drakor Dev Team

Rail Nation
simulation / management
Travian Games

Mars Tomorrow
strategy / MMORTS
Game Fabrik

Dominus
strategy / wargame
Dominus Dev Team

Monster Slayers
action / brawler
Nerdook

Legends of Honor
strategy / MMORTS
Good Game Studios

FARA
RPG / roguelike
Brian Is Creative

Tetris Fun
puzzle / tile-matching
zygomatic

Goodgame Empire
strategy / MMORTS
Good Game Studios

Bloxorz
puzzle
DX Interactive

Pixel Town
strategy / city building
automatonvx

Booty Calls
adventure / tile-matching
3X Entertainment Limited

There is no game
puzzle
Draw Me A Pixel

Might & Magic Heroes Online
RPG / MMORPG
Related Designs

Forever Space
adventure / point & click
Pinhead Games

Hattrick
simulation / management
Hattrick Limited

Bit Heroes
RPG / MMORPG
Juppiomenz