I decided to play him at his own game and use his own tactics against him.

She always manages to beat her opponents at their own game.

He is taking his own life.

He takes his own life.

He took his own life.

I am a night-owl and prefer to work during the night.

She has gone her own way and achieved great success.

He went his own way and pursued his dreams.

He goes his own way.

She is going her own way and pursuing her dreams.