I think you are going to want to use him with Mylor. The thorns would work really well and round out all of the return damage types. I don't think he will ever get an actual attack type though. I just noticed he is actually white and not neutral so you can't use Mylor. It looks like either he needs to be higher level or you have to wait for the new summoners in Chaos legion to make good use of him.
I am really hoping to get a gold version of the Witch of Warwick myself. She is my favorite gladiator at least lore wise and I need to gold version to use in my fray.
Yea! The Witch of Warwick looks sick by the way. I can immediately see the potential of this Gladiator. Magic attack disregards armour and deal direct damage. If the match condition has "Opportunity" or "Snipe", this Gladiator will be a beast! Life Leech to keep gaining health, and combo with the "Bloodlust" ability. Immediately this is a huge candidate for a rare or higher card!