Rank

"Rank" is a term that refers to the scaling of game difficulty based on player performance. In most cases, a Rank system will scale up the difficulty of the game when the player is performing well, and scale down the difficulty when performing poorly. Rank systems often influence the speed of enemy bullets and the rate at which enemies will shoot at the player, but in some cases can also influence other elements of the game, such as enemy durability and even introducing modified attack patterns. Rank systems are often operating "under the hood," meaning there is often not a GUI element in place on the screen to illustrate the player's current rank level.

Rank systems are relatively common in shooting games, with one of the most notable examples being Battle Garegga, where the Rank is influenced upward by even the most basic of player actions (shooting, your rate of auto-fire, picking up items) and is lowered by losing a life, making actions like intentionally losing a life an integral part of both scoring and survival.