His dupe makes him a pretty solid red skull counter. And in general he can handle a lot of matchups and has a lot of damage really fast. The only thing is that he relies heavily on intimidate, and it doesn't always function as it should, which hinders his usability.
I would counter and say he doesn't really "rely" on intimidate. When it works it makes it easy to get him up to 10 confidence, but it's still pretty easy when it's not working. Once you're at 10 you go unblockable after the heavy anyway. He's really good and kind of like Adam Warlock if you know him. His fighting style takes a minute to get used to but you don't lose your ramp as easy. As long as you don't get knocked down. Practice him in ROL and if you like how he works, rank him.
I will also speak against the intimidate reliance, if you know your limitations you won't struggle ramping him up at all. Guess people expect his intimidate to work like (how it used to) with Titania but Gladiator doesn't need to play so aggressively and "rely" on intimidate as hard. I don't ever remember getting hit by an intimidated AI when played normally BUT if you get too cocky and expect AI to stand still blocking while you charge a random heavy just because they have intimidate on, you are likely to get punished and that's just natural.
Overall a great, undervalued champion with really unique utility and decent damage. I'm too bored to write up paragraphs explaining the champion but he's nice. Better than overhyped Cull champion, can take Zola and Red Skull just as fine while having a lot more versatility. But again, he is undervalued and the misconception of AI/intimidate reliance exists so its better to learn from enthusiasts like Nagase, watch a guide or test him out yourself.