No Mac Version/Poor Support
The only version available now for Windows or Mac through ArenaNet is Heart of Thorns which includes the core game, Guild Wars 2.
You may be able to find a copy of Guild Wars 2 alone at your local retailer. Once you purchase a copy of the game and obtain a Serial Key, you can use that Serial Key to access the Mac or Windows version which you can download from the website.
https://help.guildwars2.com/entries/27659268-The-Guild-Wars-2-Client
Good luck.
You don’t have to buy any special “mac beta” versions of the game. You can download Mac or Windows game client once you register your serial key with your account. Simple as that…
As others have pointed out, the mac version doesn’t require a special purchase. You’re paying for an account serial, you use the serial to create an account which you can then play on both Windows and OSX. I regularly switch between…
There isn’t and likely never will be a native Mac version of this game.
The Mac game market is too small for most PC game manufacturers to do a proper port to the Mac and instead choose to use Cider to emulate the Windows specific API calls including DirectX. However if your game is big enough or your studio always treated Mac as a viable game platform (Blizzard, Bungie pre-Microsoft) or you used a game engine that natively supports Mac (is there one?) then it can happen.
For this game it’s likely that Mac support will always be “Beta”.
RIP City of Heroes