Dr. Madison Li

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

If an effect says you get one or more {E}, you get that many energy counters. To pay one or more {E}, you lose that many energy counters. You can’t pay more energy counters than you have. Any effects that interact with counters a player gets, has, or loses can interact with energy counters.

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

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

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.

Dr. Madison Li’s first ability resolves before the spell that caused it to trigger.

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.