Xenagos, the Reveler

+1: Add X mana in any combination of {R} and/or {G}, where X is the number of creatures you control.
0: Create a 2/2 red and green Satyr creature token with haste.
−6: Exile the top seven cards of your library. You may put any number of creature and/or land cards from among them onto the battlefield.

Random Encounter

Shuffle your library, then mill four cards. Put each creature card milled this way onto the battlefield. They gain haste. At the beginning of the next end step, return those creatures to their owner's hand.
Flashback {6}{R}{R} (You may cast this card from your graveyard for its flashback cost. Then exile it.)