Linear Motion Battle System

The Linear Motion Battle System (LMBS) is a fighting paradigm in video games. It is based on 2-D fighting games, such as Street Fighter and Mortal Kombat.

Most RPG games have turn-based battles, where the character(s) and the opponent/enemy take turns to fight, each picking one attack, spell, or using an item. The player controlling the characters is given time to think about what action to carry out, since the opponent/enemy cannot attack until the player has selected their action. In contrast, LMBS is real-time, so there is no dialog-driven choice (the generic fight, use item, cast spell and run away modes), and the player and opponent are constantly fighting - if the player does not press any buttons and lets the characters sit still, the opponent will continue to use attacks and the player will be defeated.

In LMBS, the fight is played in a 2-D terrain that usually stretches wider than the screen's width, so the screen can scroll to the left and to the right, depending on where the character and opponent are. Unlike fighting games, however, RPGs allow players to use items and spells, so LMBS contains a pause menu which lets the player select a spell or item. But similar to fighting games, it is possible to assign moves to buttons or carry out combination moves, to stimulate urgency and variation in battle.

In turn-based single-player RPGs, the player has to select a move for each of their party's characters during one turn of fighting. In LMBS, the player only controls one main character. Other characters in the party can be set to passive mode and not attack, active mode and attack (computer controlled), or the player can often force the characters to move or use a spell from the pause menu. In multiplayer RPG games, other party characters can be controlled by other human players.

The term LMBS is most often used to describe the fighting system in the Tales of ... series of RPG video games.