Killer whales are smart. They’ll work in packs to hunt. There’s even a video where they rush under an ice floe to cause a wave to rock the floe and dislodge a seal hiding on the floe. Clever girl!
Killer Whales are actually dolphins - really big dolphins.
Dolphins are documented to kill large pods of other dolphins that they just don’t like.
JMHO - they are smarter than humans.