This is a donator item! It is dedicated to: Woozy
The Yarn Ball is a Post-Skeletron summon weapon that can be bought from the Merchant. It spawns a Baby Kitten that scratches enemies. Like other minions, summoned Baby Kittens are invincible and follow the player for an unlimited amount of time, unless the player dies, summons a replacement minion, or cancels the buff.
Its best modifier is Ruthless. The Mythical modifier provides the widest array of stat bonuses, but these primarily affect the initial summon rather than the resulting minion. Additionally, Minions cannot deal critical hits. The only significant advantage a Mythical Yarn Ball has over a Ruthless one is knockback.