Drax

Drax the destroyer, found his dead wife and child butchered by the Kree terrorist Ronan the Accuser. Shocked and heartbroken he swore he would one day seek vengeance on their killer. He teamed up with the Guardians of the Galaxy, so he could find and kill Ronan. Together with the other guardians he succeeded in this quest. Feeling that Ronan's death is not enough avenge his loss, he swears that one day he will kill Thanos, who he believes to be the one who was controlling Ronan all along.