How to make death metal grind black hardcore deathcore vocals.

I made this video for a student i have in death metal vocals, where i discociate every kind of death metal vocals i know, i think they are all here if i forgot one tell me i'll try to put it! but i would like to have some of your comments on it, what you like or dislike! Give your point of view! Of course don't take care about the predokills at the end ahahah i don't know how to make them! Just enjoy my dummy face while i'm singing ahahah Thanx Benito And if yo