A King Penguins Worst Enemy is a Leopard Seal
People
the mongoose
myles king
dogs
A king protect their country from enemies because that is their duty as a king.
They warn enemies by opening the patch below their head and seems to be bigger in size to enemies.
it is queen cobra
Morgana and Mordred
Cleapatra the 8th
The Philistine army.
A king had to keep the nation or empire safe from enemies.
King Dedede because he can kill enemies below 50%.