Trish Manalight, Spell Thief

Hexproof, skulk.
Instants and sorcery spells you cast cost {1} less to
cast and creatures you control have haste.
Whenever Trish Manalight, Spell Thief attacks,
target player must discard a card into exile.
You may cast a card exiled this way using any
mana to pay for its mana cost until end of turn.