Guardians are hostile sea creatures, which inhabit only the seas and oceans of Minecraft. Specifically in the oceanic monuments.
Their body consists of a huge head, full of orange spikes, from which the tail-like body emerges, which they use to propel themselves. Their entire body is greenish in color, except for the spikes on their head, which are orange.
Guardian behavior
The Guardian is always swimming in the water, circling around oceanic monuments. When it detects a player or a squid, it will start following it, giving fast tail movements, and will throw a beam that will cause damage.
The Guardians will even be able to attack players when they are on top of boats or ships. Another of its ways of causing damage is through the defensive spines on its body.
Guardian spawning
The only point of Guardian generation in Minecraft is around ocean monuments, and most often inside the monument itself.
If you like this creature and in addition to details you want to get its face to make crafts or as a profile of social networks and forums, here is the Minecraft Guardian Face. You can download and print it.