Relying on super-strength too much, she doesn't see Kaa's mental assault coming and gets blindsided in her overconfidence. She falls to his hypnosis pretty quickly, and starts to float a foot off the ground as a result. Kaa wraps her up tightly, gloating over how easy it was. As he squeezes, he notices how it's like trying to crush granite. She's still practically invulnerable, despite being in a trance/brainwashed. No matter how tight he squeezes her, it's not having the effect he'd hoped. As he can't cut off her air supply, he coils her head and tries to break her neck. No luck there either. Red-faced and panting with exertion, he gives up and leaves a hypnotised Kara behind, hoping to be far away when it wears off. If she does wake up while he's trying but failing to strangle her, she'd repay him in kind and give him a lecture on being nice as she throttles him but lets him off with a stern warning as he does his best to hypnotise her again.>X-23
Conditioned as a clone to be obedient, follow orders and submit to her handlers based on scent and commands. Initial wariness and hostility melt away the second Kaa's eyes start to glow, and she regresses to her old self, dutifully sheathing her claws and letting herself be enveloped by his scaly coils. She keeps a stoic, dutiful and neutral expression while entranced, a result of her training as an assassin. She barely reacts as he starts to crush her, save for a few grunts of pain/discomfort/breathlessness. Given her conditioning, she's got almost zero percent chance of getting free from the spell on her own.
Smart, resourceful ones like Batgirl (Babs), Lara Croft and Wonder Woman (?) could see through his tricks and maybe resist or anticipate the hypnosis, and have the skill to fight back physically. Anyone have other ideas?