Senna, The Redeemer

{w}{b}, {t}: Deal 1 damage to target opponent or
creature an opponent controls, you gain 1 life
When Senna deals damage to an opponent put a
mist stack on her Senna gains +X/+0 where X is
the number of mist stacks on her at three or
more mist counters she gains First strike at six or
more mist counters she gains Reach and Lifelink
Finally. A place where I'm not hunted by death