The Prophet has indestructible as long as it has fewer than six aether counters on it.

{X}{B}, Pay X life: Put X aether counters on The Prophet. Creatures your opponents control get -X/-X until end of turn. Activate only as a sorcery.

At the beginning of your end step, put an aether counter on The Prophet. Each opponent loses life equal to the number of aether counters on The Prophet. You gain that much life. Then if The Prophet has six or more aether counters on it, sacrifice it.

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