Naturally, it doesn't get a counter itself, because an 11/11 would clearly be way too strong
Its ability, Dark Signal , is activated when from the moment you evolved your Umbreon-V to Umbreon-VMax, forcing your opponent to make one of their Benched Pokmon into their Active Pokmon, that is, you will be applying a "Boss' Orders" during that turn, being able to save a Supporter card on that turn and even saving a Boss' Orders from your hand, or use it to create a bluff in the game (depending on creativity of the situation)
Once Electro leaves the battlefield, you have until the end of the current step or phase to spend whatever red mana you have before you lose that mana as normal
Without her, I'd say this deck is dead - though Dimir still has plenty of strong options, and other ways to draw cards
You may add 2 cards with [Blue Flare] in their traits among them to your hand, and you may play 1 [Kiriha Aonuma] among them without paying its memory cost