Berserk

"You really do have talent, if you continue to train then you'll become a top warrior in just a few years. Still, that won't be fun. Following the straight and narrow path isn't really my style, and since you're my disciple I don't want you to follow such a boring path." Ren spoke as he shrugged his shoulders. 

"So let's go beyond that path. You see I noticed that there's something deep within you, that you can use as a source of power. On the surface, you might seem like a kid who's calm with pure determination, but hidden deep within you is a beast waiting to come out. A beast that would tear apart his enemies until nothing is left. Knowing your true nature, the technique I'm about to teach you is something I came up with when I first met you. I specifically made this technique just for you, so be grateful." Ren happily explained to his disciple. 

"Master, what kind of technique is it?"