The Messenger of Allah ﷺ said, "By Him in whose hand my soul rests, I would dearly love to fight in the cause of Allah and be killed, then fight again and be killed, then fight again and be killed."
قال وقال رسول الله ﷺ والذي نفسي بيده لوددت أن أغزو في سبيل الله فأقتل ثم أغزو فأقتل ثم أغزو فأقتل
Its chain of transmission is sahih. Muslim narrated it in the book of leadership, the chapter on the merit of jihad, and the rest narrated it with a similar meaning.