Flat Battle

Flat Battle (Japanese: フラットバトル Flat Battle) is a battle mode introduced in. In a Flat Battle, all Pokémon that are above level 50 temporarily become level 50, regardless of their current level; however, Pokémon below level 50 will remain at their current level.

In Pokémon HeartGold and SoulSilver, it is found at the Pokémon Communication Club Colosseum after the undefined's childhood friend ( or ) has shown them how to catch. In Generation V, it is found at the Union Room. It is similar to the Level 50 Flat rule in Pokémon Battle Revolution. In Generation VI, it is instead known as Flat Rules (Japanese: フラットルール Flat Rules) and is accessed through the Battle function of the Player Search System.

Generation IV
In Generation IV, the player can choose from several rulesets. Flat Battles are only available for Single Battles.

Generation V and VI
In Generation V, if the player sets the battle rules to Flat Battle in the Union Room, several other rules will automatically be enforced that are not present if "No Restrictions" is selected. In infrared battles, a different set of rules are automatically enforced, which are called "Normal Rules" in Generation VI; while the player is not restricted from selecting battles if they have an insufficient number of Pokémon in their party, the battle will simply become a Single Battle (if a player only has 1 Pokémon) or a Double Battle (if the player with the fewest Pokémon has 2).

In Generation VI, there are three different rule options in the Player Search System's "Battle" option: Normal Rules, Flat Rules, and No Restrictions. If Flat Rules is selected, several other rules will automatically be enforced that are not present if Normal Rules or No Restrictions is selected.