Rohirrim Chargers

You may exert Rohirrim Chargers as it attacks. (It won't untap during your next untap step.)
Whenever you exert a creature, reveal cards from the top of your library until you reveal an Equipment card. Put that card onto the battlefield attached to that creature, then put the rest on the bottom of your library in a random order.

Aurelia, the Warleader

Flying, vigilance, haste
Whenever Aurelia attacks for the first time each turn, untap all creatures you control. After this phase, there is an additional combat phase.