Yeoui (5e Equipment)
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Weapon (quarterstaff), legendary (requires attunement)
Yeoui takes the appearance of a grey bo staff that is able to grow on command to what the user says. You gain a +3 bonus to attack rolls and damage rolls made with this magic weapon.
Size Alteration. Yeoui's size can be altered according to the users will. It can grow broader or slimmer and taller or shorter at will, reaching incredible heights. When you speak a command word, the staff can expand or contract at 10ft per round.
Weight Alteration. When you speak a command word, the staff can increase or reduce its weight by 30ibs per round, though the staff may not weigh less an a quarterstaff.
Soul Bound. Yeoui can be teleported back to the wielder's location at will.
Enhanced Durability. The staff is incredibly durable, with few if any attacks able to break the staff. The staff has made of adamantine (p. 78 XGtE), which allows the weapon to score a critical hit whenever it hits an object.