Evelynne, Grave Siphon

Menace, hexproof
Whenever Evelynne attacks, you may exile a card
from your graveyard, if you do, if it was an
instant or sorcery, Evelynne gets +X/+X
until end of turn, where X is the exiled card's
converted mana cost, if it was a permanent
card, draw cards equal to the converted
mana cost of the exiled card, then discard that
many of cards.