Bree, Runaway Warhorse

Trample, haste, allied with white.(This creature
is white in addition to it's other colors.)
Warrush— Whenever all creatures you control
attack, exile the top card of your library. If it is a
land card, put it onto the battlefield tapped.
If it is an instant, enchantment or sorcery,
put it into your hand. If it is a creature, planeswalker or artifact card, Bree, Runaway
Warhorse get +4/+3 and gains first strike until
end of turn.