Moogles' Valor

Most indestructible-until-end-of-turn instants are damage control: you flash one in response to a wrath to keep your board, and you end the turn with exactly the creatures you started with. The doubling clause rewrites the job. It mints a 1/2 lifelink Moogle for every creature you already control, then blankets the whole assembly in indestructible. Ordering is the whole mechanism: the tokens are created first, so they too are covered when protection resolves, and a board of five becomes ten bodies that cannot die in combat this turn. That turns a defensive reset into a swing in board presence. The best window is your opponent's attack step. Flash it in and every attacker that trades into your line finds nothing dies, the fresh Moogles drink life off any creature they block (the lifelink lives on the tokens, not on your existing team), and the alpha strike simply fails to connect. Cast on your own turn the new Moogles cannot attack (no haste), and the indestructibility expires at end of turn, so it will not carry them safely into the crackback; the payoff there is the raw board expansion, not the protection. Five mana at instant speed sets the terms: too costly to be a casual combat trick, cheap enough to leave up as a deterrent. And the scaling is unforgiving in both directions. On an empty board it produces nothing, so it demands a committed, wide board before it earns its cost, then roughly doubles that board and makes the whole thing unkillable for a turn.