Sub-boss

In video gaming, a boss is a significant computer-controlled enemy. A fight with a boss character is commonly referred to as a boss battle or boss fight. Boss battles are generally seen at the climax of a particular section of the game, usually at the end of a stage or level, or guarding a specific objective, and the boss enemy is generally far stronger than the opponents the player has faced up to that point. A boss enemy is quite often larger in size than other enemies and the player character. At times, bosses are very hard or impossible to defeat without knowing the correct fighting approach. Bosses take strategy and special knowledge to defeat, such as how to attack weak points or avoiding specific attacks.

The first interactive game to feature a boss was dnd, a 1975 role-playing video game for the PLATO system. One of the earliest dungeon crawls, dnd implemented many of the core concepts behind Dungeons & Dragons. The objective of the game is to retrieve an "Orb" from the bottommost dungeon. The orb is kept in a treasure room guarded by a high-level enemy named the Gold Dragon. Only by defeating the Dragon can the player claim the orb, complete the game, and be eligible to appear on the high score list.

A 1980 example is the fixed shooter Phoenix, where the player ship must fight a giant mothership in the fifth and final level.

Bosses are usually more difficult than regular enemies, can sustain a lot more damage, and are usually found at the end of a level or area. While most games include a mixture of boss opponents and regular opponents, some games have only regular opponents and some games have only bosses (e.g. Shadow of the Colossus).

Some bosses require the player to defeat them in a certain way that may be unusual to normal attacks, such as using a certain weapon, or hitting the boss in a certain area. Story-centered bosses sometimes require certain prerequisites to be performed during the fight for the player to succeed, such as that a partner must stay alive during the battle or sequence.

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Wikipedia