Enemies can be configured in the database. Stats such as maximum HP, MP, skillset, strength, and the amount of experience points and gold earned after a battle with them is won can be configured in the database. Their appearance can also be chosen in the database from sprites already added to the game.
Enemies generally get stronger with better stats and skills as the player goes to progressively more dangerous locations further in the game. They generally also give a greater amount of EXP in order to incentivize players to fight progressively stronger enemies in order to level up faster.
Boss enemies are more powerful than regular enemies at a certain point in the game, usually with drastically higher HP and a skill set with unique skills not found with other enemies in the game. The increased stats and moveset generally gives a heightened level of challenge to the player. Bosses may be integral to the plot line, potentially serving as an antagonist or villain.
Generally, the boss that is defeated at the end of the game is labeled the final boss of the game. Final bosses are usually the main antagonist of the game, and may have multiple phases or forms to increase the challenge and excitement of the boss fight.
There is no one marker to set an enemy as a boss in the database, though using event commands to change the battle music and disable the ability to flee from the battle can signify to the player of a game that an enemy is a boss.