Isiah didn't even step aside while perfectly knowing that the spell he cast is going to make a lot of blood .
Robert kept rolling on the ground for a few more minutes until he just couldn't even do that anymore .
Because what was coming out of his mouth was preventing him from breathing normally .
He thought while being thrown that he could just stop moving till the effect of that spell went away .
It was not even an option for him, what came out of his mouth was very disgusting even to look at .
When Isiah cast the spell on him, he made it very clear that whatever is inside of his body is going to be outside by using his mouth as the way out .
He could have used it in a way that allowed all of his internal organs to get outside by creating a cut in his stomach but he thought of it as a safe option .