Batman and Superman faced down a team of ‘heroes’ called the Maximums who seemed to hail from another universe- it was later revealed that this world was created by the Joker (powered by Bat-Mite) and Mr. Mxyzptlk who where playing cosmic chess against each other.
Becky, an small child, had the ability to transform herself into a hulking blue monster driven by her anger. She was a member of the Maximums, an tribute/homage on the Ultimate Avengers character Hulk.
Monster inspired in someway Behemoth: his blue skin and child-like appearance were traits than belong to Monster first.
Powers: Very strong and durable.