One of the Arkentools.
The Arkenpliers belonged to Prince Ansom of Jetstone until his defeat at the Battle for Gobwin Knob, but they were never attuned to him.Erf-b1-p022 After Ansom's deathErf-b1-p131, the Arkenpliers were briefly recovered by Scarlet of the Royal Crown CoalitionErf-b1-p132, only to be lost once again when the uncroaked volcano wiped out all Royal Crown Coalition forces inside Gobwin Knob.
Powers when Attuned
Just what enormities can be expected of Wanda attuned to the Arkenpliers are unclear, but given her vocation for Croakamancy, and given that that school is the aspect of Naughtymancy ruled by the aspect of Fate, it would seem that a powerful artifact of fate in her hands is something to be feared. It is possible that the Arkenpliers greatly increase the power of the magic the attuned user casts (i.e. Wanda being able to Decrypt Prince Ansom without him deteriorating, and while keeping all of his memories and abilities intactErf-b1-p144, or being able to Decrypt large armies with little effortErf-b1-p145).
It is also possible that the Arkenpliers are a Croakamancy-specific artifact, given Ansom's proficiency with the weapon against Uncroaked and Wanda's ability to decrypt.
Real World References
It was pointed out that a company named Zhejiang Wanda Tools Co. Ltd specializes in making pliers.