Marvel's Guardians of the Galaxy

Momentum builds up during combat from any attacks that connect, and builds faster the more varied your attacks are (various ally abilities, shooting, elemental attacks, melee, etc.). If you go too long without hitting an enemy (you actually have a pretty long amount of time) your meter will start to drop pretty quickly. Additionally, certain enemy attacks (Inquisitor eye laser, for example) will automatically drop you down one level of momentum, so be careful of them. Counterintuitively, getting hit doesn't impact your momuntum meter, in general. The meter progresses as follows:
 

• Fantastic
• Amazing
• Uncanny
• Incredible
• Marvelous

For this achievement, you need to reach a Marvelous momentum ten times cumulatively. In the beginning few chapters of the game this won't even be possible, since there aren't enough enemies and you don't have many abilities. However, from around Chapter 6 or 7 onwards, fights are pretty big and enemies can take a lot more damage, so you will have many, many opportunities to reach maximum momentum. Additionally, there are many fights that involve infinitely spawning enemies. You could, if absolutely need be, farm enemies until you maximize your momentum before finishing the fight. Later fights are big enough that you can literally just shoot your gun the entire time to maximize your momentum meter, but of course any ally abilities you use will make it fill up even faster.