A group of frogs is called an army

A group of unicorns is called a blessing. 

Twelve or more cows are known as a "flink." 

A group of frogs is called an army. 

A group of rhinos is called a crash. 

A group of kangaroos is called a mob. 

A group of whales is called a pod. 

A group of geese is called a gaggle. 

A group of ravens is called a murder. 

A group of officers is called a mess. 

A group of larks is called an exaltation. 

A group of owls is called a parliament.