Kamahl's Desire
First strike out of the gate, then a swing to +3/+0 once seven cards have piled up in your bin: this aura is a graveyard escalator, and the bonus condition is what marks the era it was built for. Threshold ran underneath a whole self-mill-friendly design generation, the bet that players would happily fill their own graveyards in exchange for late-game power, and this is one of its cleanest expressions: a cheap evasion-adjacent buff before the count is met, a real beater after it. The first strike pulls weight at both ends, since a first-striking creature with three extra power kills almost anything it blocks or attacks into before it can swing back. The trade is the usual one for auras: card disadvantage that a single removal spell punishes, doubled here by the fact that you wanted that creature to be a genuine threat in the first place. What dates the card is the assumption baked into the bonus, that your graveyard would naturally cross seven cards by the midgame. That held when self-mill and cheap spells defined the format and looks quaint the moment you stop building toward the count on purpose.
