Nope. Only at the location you bought it
No I don't think so but you can use it at Hurricane Harbor
Yes you could use it only to get into six flags not the water park
Yes you can use your membership at all Six Flags parks!
Yes you can, just go to your profile on the six flags app and check on the Gold/Platinum/Diamond all parks membership and it tells you the parks you can visit.
Season pass does get you into any six flags theme parks, but depending on the pass not the water parks. So yes you can go to San Antonio six flags with your six flags season pass.
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