OneMace is a Paper plugin that enforces a global mace ownership rule: across the entire server, only one non-exempt player can own a Mace at a time (admins/OP are excluded via a permission). If the owner dies (and items drop), drops the mace, or the mace despawns, ownership is cleared and the next player who picks up a mace becomes the new owner. The plugin can also optionally block storing the mace in Ender Chests or other containers to keep the rule strict and predictable.