Foop resembles Poof, but he is shaped like a cube rather than a sphere. He also was born with a black mustache and goatee on his face, the kind typically seen on stereotypical villains or drawn on pictures as vandalism. It is interesting to note a goatee on a doppelganger insinuates its the evil one. His pajamas are slightly darker blue than his skin, and they have a skull symbol on them. Foop has bat wings and a black crown like all Anti-Fairies. His wand is a baby bottle with blue bat wings on the side, as opposed to Poof's baby rattle. He also speaks with a stereotypical British gentleman's accent like his father Anti-Cosmo, who apparently grew to dislike him soon after his birth. Foop's tears are also made of acid. He inherited the same set of fangs and pointed ears from his father, and has the same eyebrows and eyelashes his mother has.
Poof is good, while Foop is evil.
When Poof was born, it immediately turned sunny, while when Foop was born, it became stormy.
Poof has a round spherical body, but Foop has a cube shaped body.
While Poof uses a rattle to focus his magic, Foop uses a baby bottle with blue bat wings on the sides.
While Poof has no teeth, but is teething, Foop has a set of fangs like his father.
Foop has two strands of hair as opposed to Poof's one.
Poof has no facial hair, but Foop has a black mustache and goatee.
When Poof cries, bad things happen. However, when Foop cries, good things happen.
Bad things happen when Foop laughs while good things happen when Poof laughs.
He also has the standard black crown, blue skin, pointed ears, and bat wings that all Anti-Fairies have.
Foop is unpopular at school while Poof is very popular in school. (as shown in Spellementary School)
While Poof is a good basketball player and can fit himself through a basketball hoop, Foop is not a good basketball player and is unable to do the same with his square body.
Poof is an excellent political speaker (despite initially speaking using the word "poof"}, while Foop is a horrible political speaker.
Poof is close to his family while Foop prefers to do things without his family.
Foop's hair forms into the shape of an "F", while Poof's is in the shape of a "P".