Reservoir Walker

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

If a spell or ability with one or more targets states that you "may pay" some amount of energy , and each permanent that it targets has become an illegal target, the spell or ability won't resolve. You can't pay any energy even if you want to.

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