If you think it's worth the time

I mean you have a point but also his beloved brother literally died. He doesn't have special powers or anything but isn't rly the type of person to just sit there and wallow in sadness. So the way I see it, to him it was probably better to try SOMETHING at the very least even if he might die in the process, instead of just living with regret without ever learning or trying anything

If he's going to take revenge, at least be smart about it... he's going against people who's strength surpasses his own. He's just a weak puppy who can only bear his fangs... if he ended up dead due to his impulsiveness, is he able to get his revenge once he dies? He will die first before executing said revenge.

And let's say he does want to do something about it, why not investigate the people he will take revenge upon on? Plan how he will do it? He's not against people who are stupid and human. Why head charge on a battle with no weapon on him? At this rate, what he's doing is just plain suicide, not revenge.

Yeah I never said he was being smart about it He's just being emotional and acting on impulse, which isn't smart but also is something that does happen in real life as well when people are overwhelmed by events in their life