Arcane Herald

Hexproof, Mist (You may switch this creature's power and toughness until end of turn. If you do, this creature gains skulk until end of turn.)

When this creature deals combat damage to a player, you may sacrifice it. If you do, you may cast target instant or sorcery card from your graveyard without paying it's mana cost.

The gift of foresight the swift riders possess is sought after by more superstitious folks.