Velomachus Lorehold, cEDH

Flying, haste.
Whenever Velomachus Lorehold attacks, look at
the top seven cards of your library. You may exile
any number of instant or sorcery cards from
among them with total mana value less than or
equal to Velomachus Lorehold's power. You may
cast cards exile this way without paying their
mana cost until end of turn. Put the rest on the
bottom of your library in a random order.