Elesh Norn, Perfect Mommy

{t} add {w}{w} to your mana pool.
{ut}{2}{p/w}{p/w} draw 2 cards, discard one, you can only
use this ability once per turn.
At the beginning of combat on your turn you can
place a follower counter on target creature you
control: it gains lifelink, hexproof, and indestructable until the end of the turn.
If this card would leave the battlefield exile all creatures with follower counters on them instead.