I felt the urge to make a friend feel unwelcome in our group as revenge.
What did your friend do to make you take revenge on them?
I don't want him to hang out with us anymore, the dude is a terrible bore.
Friendships can be difficult and obviously you're never going to get along with everyone. However, intentionally excluding someone and seeking revenge on someone is wrong. You are just going to hurt them and make them feel bad about themselves for no reason.
I see, I won't do that again.
I'm glad you're seeing reason. Instead of seeking revenge you could use that energy to try to repair the friendship.