Tenacious Abyss-Guard

Frantic (As you cast this spell, you may exile up to
X cards from the top of your library, where X is the
amount of generic mana in this spell's mana value.
This spell costs {1} less for each card exiled this way.)
Tenacious Abyss-Guard enters the battlefield
with X +1/+1 counters, where X is the number
of cards exiled with its frantic ability.
If Tenacious Abyss-Guard has 3 or less power,
each opponent can't draw more than one card
each turn.