A herd of party poopers, a pack of grumbles, a swarm of killjoys and a shoal of sourpusses.
Angry Animals is a series of vector designs of very grumpy beasties.
You can find this collection at Society6 and Redbubble.
At Etsy the Angry Animals pop up in different versions. For example on postcards, risoprints or printed on dibond.