The killer whale or Orca(Orcinus orca; Death) is a large toothed whale that lives around the world in the oceans. It's an easily recognizable giant at about 9 meters long and 6.6 tonnes of countershaded colors. Males are larger than females and have the distinct tall, thin dorsal fins while females have shorter, curvier fins. These are highly derived dolphins with origins in the Pleistocene with extinct members of the genus Orcinus being fishers before evolving into predatory sea monsters.
The killer whale travels in mixed pods of adults and calves of both males and females. The diet varies by place. Fish such as haddock, tuna, bluefish, and any sharks, marine mammals such as other dolphins, large whales like sperm whales, minke whales, pinnipeds like seals, and walruses, and seabirds are all fair game. Killer whales are clever killers that will use tricks to hunt like rushing onto land and tipping icebergs to hunt. If one wasn't bad enough, a pack is a true terror and there are few things that can threaten a pack of killer whales. They are not known to eat humans although one should still exercise caution around these sea monsters.
Killer whales give birth like any other whale, tail first in water. Often, several females encircle the mother as she gives birth to make sure no predators get any ideas. Pregnancy lasts up to slightly over a year. Killer whales have lifespans comparable to humans.
The conservation status of killer whales is Least Concern. They are under no threat except when eating animals that have accumulated certain toxins that scale with trophic levels but there's no need to be worried about these big dolphins.
Killer whales are just that kind of animal that need no explanation and appear frequently in documentaries and aquariums but a bit less frequently in fiction. Some rumors of late surviving mosasaurs and other prehistoric sea monsters are based on skeletons of killer whales. On a weird note, the common name Orca is the species name of this whale. It's no different than calling Otodus megalodon Megalodon.