So I think Ezreal is using Kassadin’s left glove.

Now, crazy theory here but let me explain.

In game I noticed that Ezreal’s magic glove is on his left hand while Kassadin’s sword is on his right. Skimming through Ezreal’s bio, we learn that the gauntlet (and the gem inside it) are from someone named Ne’Zuk, which at first sounds very void like.

Now read this description: “He uncovered an enormous fresco of a man with Ne’Zuk’s characteristic curling horns protruding from his head”

Kassadin’s horns may not be curling, at least not currently.

And going by Ezreal’s old lore (I’m stretching I know), the gauntlet allowed him to shape the magic within him to create things. Perhaps Kassadin’s gauntlet used to do the same but broke with the void?

They also both have short range blinks. One is far stronger, but I found it to be an interesting similarity.