Honedge (5e Creature)
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Small undead, any alignment
Saving Throws Dex +4
False Appearance. While the honedge remains motionless, it is indistinguishable from a normal sword.
No Guard. At the start of its turn, the honedge can gain advantage on all melee weapon attack rolls it makes during that turn, but attack rolls against it have advantage until the start of its next turn.
Longsword. Melee Weapon Attack: +3 to hit, reach 5 ft., one target. Hit: 5 (1d8 + 1) slashing damage.
A honedge appears to be an average sword, but the spirit possessing it takes great care to dissuade anyone from this theory if they try to pick it up, violently if necessary. If two honedge meet, they will join together into one being, and their spirits will merge into one creature known as a doublade.