The Dragon - Jujunga, an intimidating indigenous Australian whose blowdarts are tipped with the deadliest poisons.
The Evil Genius - I and Am, catlike creatures with Twin Telepathy and more cunning between them than the rest of the group, Mira excluded, combined.
The Brute - Boris, a tremendous Russian who doesn't know the meaning of the word "finesse." Overestimates his own abilities; His plan for killing Jack hinged on Jack's sword breaking against his skin. Extremely dimwitted.
Evil Genius - Quicksilver/Pietro would like to think of himself this way, but whether he fits the genius part is debatable. While he is probably the smartest, the entire rest of the group is made up of D students. They do end up the Terrible Trio, after all.
The Brute - Fred/Blob. Like all of the Brotherhood, more sympathetic than usual.