He is one of the smallest Broodals. His eyes are very large and his irises is red, these are surrounded by black eyelids. He wears a green top hat which has a red ring of silver spikes. Under his hat, he has purple hair.
He wears a green suit, a white shirt, and a yellow bow tie. His body is shaped like an egg, which could be referred to as Easter eggs.
Despite being their smallest member, he leads the Broodals while Madame Broode is not with them. His Dark Side's Kingdom Brochure bio refers to him as Topper, Client Relations, and his motto is "Poise under pressure." He also seems to enjoy using his hats as weapons, as seen by their inclusion in his battles as well as his bio mentioning them. His bio also states that he is scary when he seems to be mostly hat.
Topper stacks two copies of his hat atop his regular one before skipping towards Mario. Mario must knock off his hats using Cappy to damage him; once knocked off, the hat will slide around spinning like a Green Koopa Shell, and can be hit for one heart each. He also has an attack where he spins along the ground level with the hats on his head. This attack can make him dizzy, giving Mario a good opportunity to strike. Once all the hats are removed, Topper will become vulnerable, and Mario must jump on the top of his head (though he can also be attacked directly while he is spinning along the ground). After he is hit, Topper will hide in one of his hats, and all three will bounce around like shells. At this point, Mario must hit the hat he is in to stop him, with the other hats again providing hearts. From here, the attack pattern starts over, with the exception that Topper now panics and runs instead of sitting stunned when his head is exposed. After he is hit at this point, Topper is defeated.
He is later fought again in Bowser's Kingdom. In this fight, he uses several hats instead of just two, runs away in panic when all the hats are knocked off, and must be stomped three times.
The final fight is at the Rabbit Ridge tower at Dark Side. He addresses Mario by stating that, even though Mario stopped Bowser from marrying Peach, he still has to deal with them. His strategy is the same as in Bowser's Kingdom, but now he uses even more hats.
Topper's first encounter in Cap Kingdom, as well as the first battle against a Broodal.