Defibrillating Current

In Commander, Defibrillating Current is a fringe include: the tap effect is real, but one-shot instant-speed tap at this scale rarely justifies a slot when you need interaction that scales to 40-life threats. It finds the most purpose in Izzet spellslinger decks that care about each instant cast, or ping-matters commanders who squeeze value from every point of damage dealt. In constructed formats — Standard, Pioneer, Modern, Legacy — it's too narrow; a single mana that taps two creatures is tempo-positive but the 1-damage rider doesn't trade with anything relevant, and dedicated tap-out effects with more upside exist at the same cost. Oathbreaker mirrors the Commander read: fine in the right slot, competing against stronger options almost everywhere else.