The Ruler Designer is another DLC pack announced today by Paradox Interactive, which will offer various character customization options for Crusader Kings II when it is released on April 17th for the strategy/RPG sequel. This trailer offers a look, and here's a bit:

With the new Crusader Kings II: Ruler Designer DLC all these are in your hands. Customize your character your way. Tweak and change any aspect of the character or even create an all new character and dynasty to play with. Create your portrait, change the name and dynasty and even customize your coat of arms. Change traits and stats at will and decide the size of the immediate family. The game that lets you choose your goals will now let you choose your character.