 The Guardians of the Beams keep watch over either end of the six beams that support The Dark Tower.Of the twelve Guardians the ones that are mentioned are Turtle, Bear, Fish, Wolf, Elephant, Rat, Bat, Lion, Horse, and Eagle; Maturin, the Turtle (also a character in "It"), is considered the most powerful, or significant, of these.By the time Roland was growing up, the Guardians had reached a near-mythic status, and he wasn't sure whether they even existed before running into Shardik.