'Creator' would be a unique class like Singed's Alchemist which grants one allied champion in a hex around him the Steel Origin at the start of the game (aka Viktor turning them into Battlecast version of themselves). This would solve the Lightning/Steel deficiency, which makes both of those Origins somewhat underwhelming if you don't have Lux.
Alternatively, it could be named 'Machinist' to get the steel flavor in there in case someone wonders why he doesn't also have the steel origin (which might be OP).
I'm not sure what he could do ability-wise. Any of his spells could be good while somehow making them work with Critical Strikes, following the theme of Lightning champions. E.g. He could shoot his lazer in a 2 hex line and it can 'crit' to hit again as if he had the Augment: Aftershock.
If he stands alone without anyone around him (like Yasuo in the last set), he could grant himself the Steel Origin.