Kaiju are typically modeled after conventional animals, insects or mythological creatures; however, there are more exotic examples. Choujin Sentai Jetman features monsters based on traffic lights, faucets, and tomatoes; Kamen Rider Super-1 includes a whole army of monsters based on household objects such as umbrellas and utility ladders. While the term kaiju is used in the West to describe monsters from tokusatsu and Japanese folklore, monsters like vampires, werewolves, Frankenstein's Monster, mummies and zombies would fall into this category. (Frankenstein's Monster was once a daikaiju in the film Frankenstein Conquers the World, which was created by Toho.) Kaiju are depicted as cannon fodder serving a greater evil. Some kaiju are elite warriors which serve as the right-hand man to the greater villain and are destroyed by the heroic forces. Others have a neutral alignment, only seeking to destroy buildings and other structures. During the early eras of tokusatsu, "heroic" monsters were seen in Daikaiju Eiga films, and it wasn't until later when television tokusatsu productions began using kaiju which aided the hero, saved civilians, or demonstrated some kind of complex personality. These kaiju adopted many classic monster traits, appearing as the "Misunderstood Creature."
- Main article: w:c:pacificrim:Kaiju.
Kaiju are the extra dimensional monsters that appear in the film Pacific Rim. They serve the sapient inhabitants of their dimension and come through the portal at the bottom of the Pacific Ocean called the Breach.
The Kaiju are seperated into catagories like natural disasters. There are five catagories:
- Category 1 Kaiju: The least powerful category, these Kaiju are the weakest type, often defeatable with individual tactical nuclear strikes and outmatched by Jaegers.
- Category 2 Kaiju: These Kaiju are more powerful than the Category 1 Kaiju and require greater firepower to defeat. The only known kaijiu from category 2 is onibaba.
- Category 3 Kaiju: These Kaiju are more powerful still and are a significant threat to Jaegers. The only 2 known category 3 kaiju are Knifehead and Yamarashi.
- Category 4 Kaiju: These Kaiju are incredibly powerful, usually requiring more than one Jaeger to defeat them. These kaiju would be Mutavore, Otachi, Leatherback, Raiju and Scunner.
- Category 5 Kaiju: These Kaiju are the among the most powerful of their brethren. They are extremely strong and can take huge amounts of damage while being unharmed. The only known Category 5 Kaiju is Slattern.