Awakening of Rebellion

When Awakening of Rebellion enters the battlefield, creatures you control gain vigilance
until end of turn. Whenever you cast a historic spell,
create a 1/1 white Spirit creature token with flying.
At the beginning of your end step, if you control
five or more Spirit tokens, you may sacrifice
Awakening of Rebellion. If you do, search your library for a card named "Revolutionary Spirit" and put it onto the battlefield. Then shuffle your library.