#define B_CRIT_CHANCE GEN_7 // Chances of a critical hit landing. See CalcCritChanceStage. Gen6+ chances guarantee that Farfetch'd and Sirfetch'd always get critical hits while holding a Leek and using high-crit ratio moves.
#define B_WHITEOUT_MONEY GEN_7 // In Gen4+, the amount of money lost by losing a battle is determined by the amount of badges earned. Previously, it would cut the current money by half. (While this change was also in FRLG, for the sake of simplicity, setting this to GEN_3 will result in RSE behavior.)
#define B_GHOSTS_ESCAPE GEN_7 // In Gen6+, abilities like Shadow Tag or moves like Mean Look fail on Ghost-type Pokémon. They can also escape any Wild Battle.
#define B_TAUNT_TURNS GEN_7 // In Gen5+, Taunt lasts 3 turns if the user acts before the target, or 4 turns if the target acted before the user. In Gen3, taunt lasts 2 turns and in Gen 4, 3-5 turns.
#define B_FAINT_SWITCH_IN GEN_7 // In Gen4+, sending out a new Pokémon after the previous one fainted happens at the end of the turn. Before, it would happen after each action.
#define B_UPDATED_MOVE_DATA GEN_8 // Updates move data in gBattleMoves, including Power, Accuracy, PP, stat changes, targets, chances of secondary effects, etc.
#define B_PHYSICAL_SPECIAL_SPLIT GEN_7 // In Gen3, the move's type determines if it will do physical or special damage. The split icon in the summary will reflect this.
#define B_UPDATED_CONVERSION GEN_7 // In Gen6+, Conversion changes the user's type to match their first move's. Before, it would choose a move at random.
#define B_GROWTH_STAT_RAISE GEN_7 // In Gen5+, Growth raises Attack in addition to Special Attack by 1 stage each. Under the effects of the sun, it raises them by 2 stages each instead.
#define B_SOUND_SUBSTITUTE GEN_7 // In Gen6+, sound moves bypass Substitute.
#define B_INCINERATE_GEMS GEN_7 // In Gen6+, Incinerate can destroy Gems.
#define B_CAN_SPITE_FAIL GEN_7 // In Gen4+, Spite can no longer fail if the foe's last move only has 1 remaining PP.
#define B_CRASH_IF_TARGET_IMMUNE GEN_7 // In Gen4+, The user of Jump Kick or High Jump Kick will "keep going and crash" if it attacks a target that is immune to the move.
#define B_MEMENTO_FAIL GEN_7 // In Gen4+, Memento fails if there is no target or if the target is protected or behind substitute. But not if Atk/Sp. Atk are at -6.
#define B_HEAL_BLOCKING GEN_7 // In Gen5+, Heal Block prevents healing by Black Sludge, Leftovers, Shell Bell. Affected Pokémon will not consume held HP-restoring Berries or Berry Juice.
// Draining abilities will not heal but will prevent damage. In Gen6+, Heal Block prevents the use of most HP-draining moves.
#define B_ABILITY_WEATHER GEN_7 // In Gen6+, ability-induced weather lasts 5 turns. Before, it lasted until the battle ended or until it was changed by a move or a different weather-affecting ability.
#define B_STANCE_CHANGE_FAIL GEN_7 // In Gen7+, Stance Change fails if the Pokémon is unable to use a move because of confusion, paralysis, etc. In Gen6, it doesn't.
#define B_SHADOW_TAG_ESCAPE GEN_7 // In Gen4+, if both sides have a Pokémon with Shadow Tag, all battlers can escape. Before, neither side could escape this situation.
#define B_SYNCHRONIZE_NATURE GEN_8 // In Gen8, if a Pokémon with Synchronize is leading the party, it's 100% guaranteed that wild Pokémon will have the same ability, as opposed to 50% previously.
#define B_SYNCHRONIZE_TOXIC GEN_8 // In Gen5+, if a Pokémon with Synchronize is badly poisoned, the opponent will also become badly poisoned. Previously, the opponent would become regular poisoned.
#define B_UPDATED_INTIMIDATE GEN_8 // In Gen8, Intimidate doesn't work on opponents with the Inner Focus, Scrappy, Own Tempo or Oblivious abilities. It also activates Rattled.
#define B_STURDY GEN_7 // In Gen5+, Sturdy causes the Pokémon to have 1 HP remaining if another Pokémon's attack or confusion damage would have brought it from full health to 0 HP.
#define B_PLUS_MINUS_INTERACTION GEN_7 // In Gen5+, Plus and Minus can be activated with themselves and the opposite ability. Before, only the opposing ability could activate it.
#define B_HP_BERRIES GEN_7 // In Gen4+, berries which restore hp activate immediately after HP drops to half. In Gen3, the effect occurs at the end of the turn.
#define B_BERRIES_INSTANT GEN_7 // In Gen4+, most berries activate on battle start/switch-in if applicable. In Gen3, they only activate either at the move end or turn end.
#define B_CONFUSE_BERRIES_HEAL GEN_8 // Before Gen7, Figy and similar berries restore 1/8th of HP and trigger at half HP. In Gen7 they restore half HP, triggering at 25% HP. In Gen8 they heal 1/3rd of HP.
#define B_TRAINERS_KNOCK_OFF_ITEMS TRUE // If TRUE, trainers can steal/swap your items (non-berries are restored after battle). In vanilla games trainers cannot steal items.
#define B_SOUL_DEW_BOOST GEN_7 // In Gens3-6, Soul Dew boosts Lati@s' Sp. Atk and Sp. Def. In Gen7+ it boosts the power of their Psychic and Dragon type moves instead.
#define B_FLAG_INVERSE_BATTLE 0 // If this flag is set, the battle's type effectiveness are inversed. For example, fire is super effective against water.
#define B_FLAG_FORCE_DOUBLE_WILD 0 // If this flag is set, all land and surfing wild battles will be double battles.
#define VAR_TERRAIN 0 // If this var has a value, assigning a STATUS_FIELD_xx_TERRAIN to it before battle causes the battle to start with that terrain active
#define B_FAST_INTRO TRUE // If set to TRUE, battle intro texts print at the same time as animation of a Pokémon, as opposing to waiting for the animation to end.
#define B_WILD_NATURAL_ENEMIES TRUE // If set to TRUE, certain wild mon species will attack other species when partnered in double wild battles (eg. Zangoose vs Seviper)
#define B_AFFECTION_MECHANICS FALSE // In Gen6+, there's a stat called affection that can trigger different effects in battle. From LGPE onwards, those effects use friendship instead.