If you're looking for another name for the Memory, maybe the [Splitting Image]?
A sword that can split/slice things in two, whilst also being wordplay on 'spitting image', since the sword perfectly reflects things. :)
The devils mirror myth fits this a lot. Mostly about the part how it shattered. which could lead to some myster on if he breaks the sword it could be really fun. The name twisted reflection, Broken Deal, devils deal
proficient to expert with first and second sword. Now needs to practice with his new toy and all it's attribute. Sunny is growing up in the ascended world. Onward to practice and Shipwreck island.