What is A Sandbox game?

[Whero]

It said can’t join a sandbox game as a non sandbox character. I’m just curious what is Sandbox?

 

[Usagi]

Is PSO old to you? (Sandbox mode added!)

Although PSO is new to some, PSO may be old to many others. Some people may not like the idea of starting on a new server at level 1 again. Some people may also like to experiment with different character builds and equipment, but don't like the idea of having to put in so much time to do so...

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