Monster eggs have a white body with some light gray shading, and lines here and there suggesting some mummy-like bandage all over. They also have a pair of pointy fangs, dark eye sockets and black and white eyes. Here is the description the game gives:
"The LIMITED TIME Monster Egg is only available to adopt during the spookiest month of the year (Ends Nov 3rd). Monster Eggs are naturally healthy but do get pretty grumpy. *Unlocking this egg makes it available year round*"
Monster eggs cost 30,000 coins, hatch in 6 days, and their difficulty is two and a half out of four eggs.
Monster Egg Creatures
Neutral-
Nerdy-
Pretty- turns into a Duskula. This is a white bat-like creature with no wings, pink paws, forehead and ears, and a long dark red cloak recalling that of a vampire in the neck collar shape. It will give you Ultimate Chocolate Truffle (Food Item) every 7 hours 4 minutes. Bio: "Nocturnal and shy, a Duskula is often found listening to classical music and reading novels by candlelight."
Cute- turns into a Lagulli. This is a green creature with fins for hands and on its cheeks, and a body covered in seaweed. It will give you Sundae of Pure Ecstasy (Food Item) every 11 hours 25 minutes. Here's the bio: "Known for its friendly and social nature, this slippery cutie is often found in neighborhood ponds and at the bottom of public fountains guarding the wish pennies."
Athletic-
Dark- Turns into a Murkler. It has a typical "bed sheet with holes for eyes" ghost look, but it's black, and a pair of glowing yellow eyes is visible through the holes. It will give you a Forbidden Apple (Food Item) every 2 hours 26 minutes. Bio: "Murklers are so self conscious that they refuse to take off their sheet and let any other creatures know what they look like. Your guess is as good as ours. (They might be invisible??)"