Is Jayce left handed or right handed?

For some reason in the splash at, Jayce holds the hammer as if he was right handed. However in game, he holds the hammer as if he was left handed. Likewise, the wiki seems to also differ from ingame, "Jayce appears to have a dominant left eye and a dominant right hand, as he holds his cannon at the base with his left hand, as a left eyed person would with a rifle regardless of left or right hand dominance, while he holds his hammer with his right hand near the top of the hammer as a right hander would" (directly from the wiki).