I found some more browser games that weren't on this list, and I wasn't sure how to add them. They meet the criteria you outlined:
A3: Dragons Kingdom: Resurrection - Pick your class and explore the world in search of the dragon that is destroying everything you hold dear. Earn/create weapons/armor, gold - use magic. Build guilds, houses, fortresses, and band up with others online to kill the dragon - don't try to do it on your own!
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A3: The Legend of the Green Dragon - Pick your class and fight others online. Learn from your trainer to level up etc. Earn up gold to buy new weapons and armor.. A Classic!
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A3: The Merchant - Search the stars with other players in this space trade game. Learn the economies and politics to stay alive. Make sure you upgrade your weapons and armor before you venture too far...
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A3: Net Pet - You are a pet trainer and must fight your pet to survive. Build up the pet's attributes. Whats different about this game? The pets can use weapons, armor, and magical items!
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