Mascot

Mascots are costumed NPCs who appear in The Sims: Vacation, The Sims 2: University and The Sims 3: University Life.

Vacation mascots
Vacation mascots appear on Vacation Island lots and interact with children. Unlike the other Vacation NPCs, mascots arrive in the morning and leave at night. Each area of Vacation Island has its own mascot. The snowy mountain area has "Betty Yeti," the forest area has "Archie Archer", and the beach area has "Marky Sharky". The only difference between these three characters is the costume.

Mascots will follow kids around and try to get their attention, often with little regard to whatever the kid may be doing at the time. Mascots will often want to hug kids, but a kid who is in a bad mood may respond by hitting or kicking the mascot.

University mascots
There are two types of costumed university mascots. One is the llama mascot, who is essentially a costumed male version of the cheerleader. The other is the evil mascot, who is dressed as a cow. The cow has few, if any, body points, while the llama mascot has the body skill maxed out. If both of these mascots appear on the lot, they will most likely get into a fight.

There are three of each, and it appears that each college lot, both residential and community, is assigned its own llama mascot and evil mascot. However, this is not obvious, as mascots are rarely seen out of costume. Mascots will change out of their costumes when swimming, or when doing things such as using exercise equipment or soaking in a hot tub.

Like other college NPC's, mascots are always freshmen.

If a mascot is added to a household, the game will generate a new one. Mascots will become playable when added into a household, and will be able to graduate, but their behavior will retain some NPC characteristics even after graduation. A mascot who graduates and is moved into the neighborhood may still visit campus, and may still walk into other Sims' homes without being invited.

The Evil Mascot
Unlike the llama mascots, who are always male, an evil mascot (identifiable by the cow costume) can be either male or female. He or she will come into a dorm, house, or Greek house and pull pranks, fight with, flirt with or otherwise generally annoy the Sims who are there. (This is because all evil mascots have the same personality; they are completely Outgoing and Playful but have no other personality points, which gives them a strong tendency toward aggressive social interactions such as poking, shoving and even belching at any Sim they see.) One of the two ways an evil mascot can wreak the most havoc is by setting off a sprinkler, which makes a large mess that will have to be cleaned up. The other way is by flirting with a Sim while the Sim they are in love with/engaged to is watching. This will cause the other Sim to become furious at their significant other and effectively destroy the relationship. However, anything an evil mascot is preparing to do to a playable Sim can usually be canceled from that Sim's action queue.

Evil mascots may call Sims all the time to bother them, even after they graduate, but this is not peculiar to them. According to the Prima Guide for University, the evil mascots are from a rival school, although this is debatable since they can be called by using the Campus Directory that is available on phones in college sub-neighborhoods.

An evil mascot will leave a residential lot if told to leave by a playable Sim. However, the "Ask to Leave" interaction will generally not interrupt any mischief that the evil mascot is preparing to do; the playable Sim may spend some time chasing the evil mascot around the lot before finally being able to tell the evil mascot to leave.

An evil mascot may have some points in the Body skill, but both the llama mascots and the cheerleaders have the Body skill maximized. So, when evil mascots get into fights with llama mascots or cheerleaders, they nearly always lose.

If Open for Business is installed, and a SentryBot is present, it will shock the evil mascot.

An evil mascot who appears on a community lot may use the lot's facilities in the same way as any other college Sim, but is more likely to try to cause mischief.

An evil mascot who is added into a household can perform the school cheer and have special clothing like the llama mascots.

Trivia

 * If the player has Apartment Life, a mascot can be summoned using the boolprop testingCheatsEnabled true/ via the mailbox, even if University isn't installed. However, without University, there is no mesh for Mascots and the summoned Sim will be an Adult Sim in normal clothing, with the 2nd face template.

The Sims 3: University Life
Like its counterpart in The Sims 2, University Life also features a mascot wearing a llama costume. However, the mascot in University Life can be either male or female, and there are no evil mascots.

The mascot's function is largely related to school spirit. With a high enough relationship, a Sim may ask the mascot to teach him/her a dance. In addition, if the university pack isn't available at the house (e.g. due to just getting the expansion pack), a mascot will be summoned to the active family's household, dropping the university pack from which the active sims can get items and/or take the placement tests.