um, havent done anything with trolls. but,...
first is a little odd. vigilance and lifelink are white abilities. not only that but it makes him a little OP when you are gaining 12 life a turn and then 6 life on their turn in a block. that may be on par with some other life gain stuff, but i would at least require naya colors for it to even have lifelink or vigilance. (I would pick one or the other, even then.)
2nd one looks perfect. again, not really familiar with Troll combos. could remove trample, but that's a nit-pick, since he's legendary.
love the flavor text. <3