Near death experiences have allowed you to become stronger, the thrill of fighting for your life pushes you to your limits.
Momentum allows the user to gain combat benefits as long as they stay in the flow. Once you make an attack followed by casting a spell you enter the (flow or vice versa). To stay in the flow you can't attack or cast a spell twice in a row. You gain the following benefits
Momentum 2 - You are no longer slowed by difficult terrain and creatures have disadvantage on opportunity attacks against you.
Momentum 4 - ????
Momentum 6 - ????
Momentum 10 ????