This class has access to limited psionic spells, plus mantle powers.  Highly versitile throughout the build.  I'd say T2 or T3
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what book is this from? will look into it when i can.

Ardent is Complete Psi

If we're going T2 or T3, I'd definitely say T2. This reminds me an awful lot of cleric domains with psionics. you get a domain power + the casting from said domain(s). yes it's restricted to how many powers you can learn from what "domain" but you get to choose whatever mantles you want, so it's entirely customizable. definitely say T2

-Z

Z - I've been thinking on this....with only level 6 spells, is this class a t2 qualifyer?  T2 usually implies ZOMG broken power.  I think this class is strong.  very strong.  I'm just not sure if his powers break the game.  I think that might be a limiting factor.  Thoughts?

this has 9th level psionics. tier 2. the divine mind is restricted to 6th level spells, the ardent is not. at 17th level they gain the ability to pick up 9th level manifestations from their mantles. 

to clarify: 9th level spells/psionics is more often than not game breaking. While it varies from campaign to campaign (eg: some campain settings have magic nerfed hardcore so as things like every spell cast gains you corruption and/or madness), generally speaking 9th level spells are going to unbalance things in one way or another. Rules as written, many lower level spells can become world altering, but most of that depends on the ingenuity of the player and the world around them (and how badly that player wants the DM to throw a book in their face). 

"At each additional level, an ardent learns one new power from her available mantles. She must be able to manifest the new power at the level at which she learns it, however. For example, an ardent who attains 5th level can learn any power from one of her mantles that costs 5 power points or less to manifest; she cannot learn a power from a mantle that costs more than 5 power points to manifest until she attains a level capable of manifesting a power with that cost." (aka 9th level psionics at 17th level)

ardents get full power point advancement, and because of that, i see no reason for it not to be a tier 2 class. it's certainly no wizard/cleric/druid, but it's certainly capable of fucking over a world.

Noted.  Tier 2 it is