Tengu is the most obvious choice for a new playable race. The rush of newly created tengu can be written in the lore as the opening of their sealed off area, they already have a big enough starter area that is conveniently located near other low level areas, and with already built access to those points (there are several closed gates that would lead to the Tengu area).
Kodan would be a nice second choice (and I’d play one in a heartbeat), but would be harder to accomodate. First you’d need a way to explain where all those new kodan are coming from, can be done by talking about a new iceberg city appearing and acting as their starting area, but the main problem I see with them is that they’d need significant areas of the map opened for it, since the areas where a new kodan ship would appear are to the north, where it’s in contact with high level areas. Still could be done kinda like how they did with the blood elves in WoW, they got two new low level areas that were connected to a high level area, but at their city they could teleport to the undead city, that had more low and mid level areas to level up nearby, so an asura gate directly to LA would solve that (and maybe one to Hoelbrak, since Kodan already have ties with the Norn).
Largos, I don’t think it might work too well as a next race, at least for the time being. I do agree they’re a really cool race, a race of masked stealth underwater assassins. Thing is, several of the things they make them “cool” also makes them hard to use as a playable race. Big part of the whole aura of mistery around the race is because we don’t know how they really look like behind the mask, the moment we can create one that is dispelled, not to mention that to keep within their current lore you’d need to either limit their head armor to their masks or just let them show their faces. Second, the stealth… giving stealth to a race as a racial could end up being OP with several professions. Third I see is the enviroment, they’d need an underwater (or underwater heavy) area to be their starting cities, which would be cool by itself, but would need a serious revamping of underwater combat in several professions. Largos would be really good as a race, but IMHO the effort to make them playable is way bigger than with other races, which I think would probably put them back as a priority.
Centaurs would be good, but I doubt we’ll get to play any of the krytan variety, too much bad blood between them and the humans (though the same could be said about the charr), but probably if we get to Elona… after all we did have an elonan centaur as a hero in GW1. That said, making them a playable race would need a MAJOR rebuild of all armors, not something to be taken lightly.
The other minor races (Quaggan, Hylek, Skritt, Ogre…) I doubt they’ll become playable mainly because they’ve usually have severe limitations in lore for them to become playable (all ogres having pets as it’s part of their culture, skritt needing other skritt around for intelligence and so on).
It’s a pile of Elonian protection magic, mixed with a little monk training,
wrapped up in some crazy ritualist hoo-ha from Cantha.
A real grab bag of ‘you can’t hurt me. They’re called Guardians.
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