This helps advance the story of the whole neighbourhood instead of only the active playing unit's. Sims live for a set duration of time that is adjustable by the player and advance through several life stages (baby, toddler, child, teen, young adult, adult, and elder). Sims can die of old age or they can die prematurely from causes such as fire, starvation, drowning, electrocution. The primary world in the game is Sunset Valley (in the console version, the main world is Moonlight Bay), while an additional world called Riverview can be obtained for free. All expansion packs to date (except and ) have included a world, and additional worlds can be bought at The Sims 3 Store for sim points. Career opportunities like working overtime or completing tasks can yield a pay raise, cash bonus, or relationship boost. Challenges occur randomly based on each Sim's lifestyle, like relationships, skills, and jobs. Skill opportunities are the requests by your sim's neighbors or community members for Sims to solve problems using their acquired skills for cash or relationship rewards. The new reward system Wishes replaces the Wants and Fears system in its predecessor "The Sims 2". Fulfilling a Sim's wishes contributes to the Sim's Lifetime Happiness score, allowing players to purchase lifetime rewards for the cost of those Lifetime Happiness points. The game introduces a big change in terms of customization with the "Create-a-Style" tool. In this way, every object or piece of clothing in the game is completely customizable in terms of color (which can be picked from a color wheel), material (plastic, stone, fabric, wood...) or design pattern. "The Sims 3" introduces many more character customization options than its predecessor "The Sims 2". Like the previous game, the player can customize age, body build, skin color, hairstyles, clothing and personality. A new life stage is included between adolescence and adulthood: young adulthood. This stage was introduced in "The Sims 2" only during university period, but is now the main life stage for the game. Additional options were added in expansions and updates, for example tatoos, breast size and muscle definition. "The Sims 3" offers a wider range of skin tones than its predecessors, ranging from realistic Caucasian and black skins to fantasy green and purple colors. The game builds upon a new personality system. As opposed to previous games, where personalities consisted on sliders, and a limited set of personality points to distribute among them, "The Sims 3" introduces a trait system: adult sims can have up to 5 personality traits to pick from a list.