Reaper's Crescent

The blade of this alabaster +1 striking sickle grows thick and pitted as the moon waxes, and it thins to a sharp sliver as the moon wanes. Moonlight also causes a second rune on the blade to change shape with the moon's phases: during the new and crescent moon, the weapon has the rune; during the quarter moon, the rune; and during the gibbous and full moon, the rune.

When wielded under moonlight of any strength, the reaper's crescent deals additional cold damage equal to the number of damage dice.