mountain
aether vial (at the beginning of your upkeep, put a charge counter on it, you may tap and cast a creature spell for free if it's mana cost is equal to the number of charge counters on it)
turn
aether vial (at the beginning of your upkeep, put a charge counter on it, you may tap and cast a creature spell for free if it's mana cost is equal to the number of charge counters on it)
turn