Shard of Betrayal, Least (3.5e Equipment)
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Least Shard of Betrayal: This ink-black crystal has the vague silhouette of a jagged dagger.
Priests of roguish deities craft shards of betrayal to aid their chosen blackguard and others in sending their enemies to their final resting place, no matter their type.
A weapon with this crystal attached deals an extra 1d6 points of damage on a successful sneak attack, and the weapon's critical multiplier increases by one step (from ×2 to ×3, for example).
Moderate (DC 21) necromancy;CL 5; Craft Magic Arms and Armor, greater mighty weapon, wraithstrike; Market Price: 5,000gp