Hopeful Eidolon

Every keyword needs a card that shows its arithmetic in the plainest possible terms, and this is bestow's rate-floor made legible. Auras have always carried a hidden tax: they collapse two cards into one, so a removal spell aimed at the host takes both. Bestow answers that not by delaying the attachment but by making the mode a choice at the moment of casting. Pay one white mana and it resolves as a lifelink Spirit that trades and squeezes out a point or two of life. Cast it for its bestow cost instead and it comes down as an Aura spell, a +1/+1 lifelink buff that keeps its own hide: kill the enchanted creature and the Eidolon detaches and stands up as a 1/1, so the removal that would have two-for-one'd a normal Aura only ever nets a single card. That resilience is the whole justification for deploying it at the Aura rate. The two grants work in concert. The +1/+1 widens the host's combat math, and the lifelink converts each extra point of damage into life, so a modest attacker becomes a clock that stabilizes you while it swings. None of the numbers dazzle on their own, and that restraint is the point: it is the baseline demonstration of a keyword built to make Aura-style buffs worth the deckbuilding gamble, the insurance-policy version you reach for when you do not want to pay for a marquee effect.