Betrayed and their regret

Natsu will do for his friend everything. He started playing dumb and hid his true power because he was afraid that he will hurt someone. But Fairy Tail mages started laughing at him, saying that he was unmature, dumb and idiot. They betrayed him. Natsu was heartbroken. Just one thing was on his mind: Revenge.
He wants to kill them all. Every last one of them.