He has killed dozens of zombies so far and has only obtained three crystals. I said in the last chapter that he has obtained a lot of crystals and also how long will he stay in school?
Bro, you know the things of the Chinese, the tailed monster can wipe out an army, he cannot face MC and he is afraid and needs the help of his entire village.
Unable to master the complete tail-beast transformation yet, he couldn't deploy it at will.