why is gaara so badass

Well first of all he's just really strong second he is a jinchuriki so he doesn't follow the rules until he becomes the kazekage and he looks strong, elite and he is a warrior

because hes a monster and has the shukaku inside of him plus hes a beast

he is because he was born with a demon inside of him and he just wants to be loved... (spolier)....(note the LOVE symbol on his forhead)

if you know what his name means you would have never asked this question.

just cause....

First of all, he's silent, and has sand, he's an elite warrior, he is a Jinjuriki . He use to be a killer .