This achievement is accumulative, so you can do as many matches as you want, you have to use any Drive move using the D button, the easiest way to achieve this is spamming → D quickly in the corner with a second controller, so the character dont tech and the combo scales so much that the life bar dont drop anymore, so you can spam until the achievement pops up. A way to make the process fun: You can choose Iron Tager as the second player, drop Ragna's life quickly with his command grabs and hurt him until his life is to the minimum. Ragna's health is 10,000, so you can refill Ragna's lifebar to the maximum and then drop it again with Tager. This make easier and more fun, because you only need to refill his life 10 times and dont guess how many hits you have left of blood drain.