What I read somewhere (from diabloII.net) i believe.. characters from 1.09 and 1.10 can't play together, although you can play characters from both versions you won't be allowed to use characters from 1.10 with 1.09.. so it would be like trying to join a hardcore game with a softcore character so you will haev to make a new character to play new 1.10 games..
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