How to Build an Assassin Character for Third Edition Dungeons and Dragons

Consider the route your character will take to be eligible for the assassin prestige class. Some base classes will be able to take levels in the assassin class much earlier than others, but these classes may not match with the concept you have for the character and her advancement. A fighter assassin will have a lot more ability to do large amounts of damage in combat by flanking and using a sneak attack, while a wizard or sorcerer who becomes an assassin will have all of his spells to assist in sneaking around and completing his missions.

Check the prerequisites for the assassin class, and make sure to add those skills and follow those guidelines while you gain in levels in your character's base class.

Choose stealth-oriented skills and abilities for your character's base class. To quality to become an assassin, a character must have a minimum of eight ranks in the "move silently" skill, eight ranks in the "hide" skill and four ranks in the "disguise" skill. These are all class skills for the rogue class, and since the maximum rank a character can have in a class skill is three plus the character's level, a rogue character will be eligible to become an assassin by level five.

Give your base character an intelligence score of at least 14. The assassin gains the ability to cast some arcane spells, but the character will need to have a 14 intelligence to be able to utilize all of them. Because the assassin's spell-casting abilities are tied to the intelligence score, a wizard base class can make an excellent assassin -- although it will take longer to get there, as the skills required are considered "cross-class" for a wizard. To acquire all the necessary ranks in the "move silently," "hide" and "disguise" skills, a wizard would have to be at least 13th-level.

Act according to the proper alignment. An assassin must have an evil alignment, although there are no restrictions as to to the law and chaos side of the alignment axis. Any given assassin can be lawfully evil, neutrally evil or chaotically evil.

Work with your dungeon master to decide how your character will become an assassin in the context of the current campaign's storyline.