If you upgrade your account to VIP (by subscribing), you have access to all the zones EXCEPT the 4 expansions for the length of your subscription. If you buy the expansion without going VIP (or you stop subscribing), you'll have access to the expansions but not the non-expansion zones, some of which you'll want to have to level between 30 and 50 (when Moria picks up).
Originally Posted by Cucchi_andrea
There is no "basic game" to buy anymore. Maybe you are referring to buying the "All Quests Pack", which purchases all the non-expansion zones that you don't already get for free. If you were to do that, then there would be little else you'd get for going VIP and you could consider staying Premium, which is an upgrade from Free and comes with ANY purchase you make with Real Life money, no matter how large or small.
Hopefully this answers your question.
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