Last Breath

In Commander, Last Breath is a narrow but reliable answer to mana dorks, small value creatures, and infinite-combo pieces that tend to sit at power 2 or less — the exile clause matters when graveyards are part of the plan. The 4 life gifted to an opponent rarely swings a game with 40-life starting totals, making the downside easier to stomach here than anywhere else. In Pauper, it competes in a format full of small creatures and sees occasional play as a clean exile effect at common. Modern and Legacy have removal with fewer strings attached, so Last Breath doesn't make those cuts outside of very specific shells. Pioneer sits in the same boat — functional, but outclassed.