King of Shooting BonusEarned more than 10 million points for shooting into a single enemy.
In many shoot'em up games, you can earn some score for just shooting on enemies, without destroying any parts of it. These points are minimal compared to the scores for destroying, but can add up to a considerable amount if you intentionally try to get it.
This achievement requires to make a good amount of this bonus. The conditions to make a good score with shooting are fairly simple. The fight against the enemy must be long, else the enemy dies before you could earn 10 million. Also, I suppose you must have good Soul Gauge multiplier too.
Basically, only bosses of each stage satisfies these condition (some mini-boss of later stages might also work). And by the nature of the long fight required, I don't think there is some easy answer to this. You must expect some hard fight.
For example, if you fight stage 2 boss with Yun (blue) having x30 multiplier and didn't used bomb in the fight, I believe you will be able to unlock this achievement. You can die in the fight, but can't continue since continues resets both your score and multiplier.
You can also do this on stage 1 boss if you enter the boss fight with a good multiplier value and prolonged the fight. The top players on the online leaderboard are doing this, so check up their replays.
(NOTE: Translations of achievement name or text in this guide are not official and might be wrong.)