Inaction Injunction

Point it at the threat that would have swung, and you trade two mana for a turn of breathing room plus the card that pays the spell back. The detain clause is a one-turn freeze rather than removal: until your next turn the creature can't attack, can't block, and can't use its activated abilities, then it walks free. That last part is the wrinkle that makes this sharper than a combat trick. It doesn't just deny a swing or a block; it blanks a sacrifice outlet, a pump ability, or a mana-tapping body for the window it takes to stabilize, which is exactly when those activations would have mattered most. The cantrip is the load-bearing piece. A delay button that replaces itself never falls behind on resources, so the math comes down to one question: is the turn you're buying worth more than the card you'd otherwise be holding? When a blocker is about to fold or an alpha strike is loading up, it usually is. This is the soft-answer school of blue tempo, the lineage that defers a problem instead of solving it, and the detain keyword is its tidiest expression: a deliberately bounded interruption, calibrated to a single turn cycle, attached to a draw so spending the tempo never costs you the card.