Bent on something/on doing something
Definition 1 of 1
Pro Tip 1/3High Commitment
Expresses a very strong determination or unwavering purpose. 
She was bent on becoming a doctor, no matter the obstacles.
Pro Tip 2/3Emotional Intensity
Implies an emotional drive or personal investment in an action or goal. 
He's bent on proving them wrong and regaining his honor.
Pro Tip 3/3Possible Negative
Can suggest stubbornness or obsession when used in certain contexts. 
Ever since the argument, she's been bent on getting revenge.