The ability specifies only once per turn, but if the character is bounced back to hand/discard and returned to the board, it counts as a new glimmer
Sword of the Squeak With rats and squirrels continuing to become more viable creature types to build a deck around, Sword of the Squeak likely finds its way into more and more decks over time
Meanwhile, you tap them and use them for mana all nice and neat
More than likely though, youll be splashing into more than one colour with common identities being Izzet (blue and red), Grixis (blue, black, and red), Azorius (white and blue), and Esper (white, blue, and black)
The biggest knock against Unsettled Mariner is the fact that it is likely difficult to find room for multiple copies, but the ability to protect your creatures (and yourself) from spells your opponents cast is potentially quite valuable