Aether Meltdown

Some triggered abilities that state that you "may pay" a certain amount of {E} describe an effect that happens "If you do." In that case, no player may take actions to try to stop the ability's effect after you make your choice. If the payment is followed by the phrase "When you do," then you'll choose any targets for that reflexive triggered ability and put it on the stack before players can take actions.

Some spells and abilities that give you {E} may require targets. If each target chosen is an illegal target as that spell or ability tries to resolve, it won't resolve. You won't get any {E}.

Some triggered abilities state that you "may pay" a certain amount of {E}. You can't pay that amount multiple times to multiply the effect. You simply choose whether or not to pay that amount of {E} as the ability resolves.

{E} is the energy symbol. It represents one energy counter.

Energy counters aren't mana. They don't go away as steps, phases, and turns end, and effects that add mana "of any type" can't give you energy counters.

Energy counters are a kind of counter that a player may have. They're not associated with any specific permanents.

If the target creature or Vehicle becomes an illegal target while Aether Meltdown is on the stack, Aether Meltdown won't resolve. It won't enter the battlefield and you won't get {E}{E}.