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Elemental Forums
Also, what determines which traits I'm allowed to choose from at each level up? Is there a list of all the traits? Couldn't find it in the hiergawhatshisname.
The traits you get available is randomly selected from the list.
Common traits show up more often than uncommon, and uncommon show up more often than rares.
There is an exception at level 4, where you will have to select between one of 5 paths for your hero.
Also some traits have special prerequisites, "Lethal 1" requires for you to enter "Path of the Warrior" before it have a chance to pop up.
I have no knowledge of an easily accessible list.
Sincerely
~ Kongdej
because only 5 traits appear when you level up, there is some randomness to it, although there are tarits that every hero can get, and then there are path dependent ones that only unlock once you get the path.
a common trait has a better chance of appearing than a rare one. Perhaps someone else could give you the percentages, but now that version 1 is out we can make a wiki with this info.
edit oh kong you beat me lol 
"Profession" Paths are also considered rare, and can pop-up again later. I've seen more profession pop up after initially choosing Defender of Governor, if not anything else.
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