Whenever Aetherwind Basker enters the battlefield or attacks, you get(an energy counter) for each creature you control.
Pay: Aetherwind Basker gets +1/+1 until end of turn.
2/9/2017 The triggered ability triggers both when Aetherwind Basker enters the battlefield and whenever it attacks. You don’t have to choose only one.
2/9/2017 Abilities that trigger “whenever you get one or more ,” such as that of Fabrication Module from the Kaladesh set, trigger only once as Aetherwind Basker’s triggered ability resolves.
2/9/2017 is the energy symbol. It represents one energy counter.
2/9/2017 Energy counters are a kind of counter that a player may have. They’re not associated with specific permanents. (Other kinds of counters that players may have include poison and experience.)
2/9/2017 Keep careful track of how many energy counters each player has. You may do so by keeping a running count on paper, by using a die, or by any other clear and mutually agreeable method.
2/9/2017 If an effect says you get one or more , you get that many energy counters. To pay one or more , you lose that many energy counters. Any effects that interact with counters a player gets, has, or loses can interact with energy counters.
2/9/2017 Energy counters aren’t mana. They don’t go away as steps, phases, and turns end, and effects that add mana “of any type” to your mana pool can’t give you energy counters.
2/9/2017 You can’t pay more energy counters than you have.