He's shit at the moment to be completely honest, He's like a paladin class, he can heal and stuff but there are other frames that do what he does better.
SpmSL | Deeza445 | Pidda | Hush | Butler | Mongius | Reta | Kamura | Sheik
SrCheetah: I fucked my hand badly once because of an asshole
Mastery Rank 2? You get access to trading, syndicates come into play at mastery rank 3 and the level of your mastery rank is the amount of trades you get per day. Mastery Rank 3 unlocks a few weapons as does 4, 5, 8 and 12.
SpmSL | Deeza445 | Pidda | Hush | Butler | Mongius | Reta | Kamura | Sheik
SrCheetah: I fucked my hand badly once because of an asshole
Not really much to tell, you have to trade something to get something, and depending on the rarity or w/e of the thing that is being traded their is a base credit tax for each item that you have to meet. That's about it.
SpmSL | Deeza445 | Pidda | Hush | Butler | Mongius | Reta | Kamura | Sheik
SrCheetah: I fucked my hand badly once because of an asshole