The homestanding Katz, playing in their brand-new gymnasium, got 14 points apiece from Chase Massey, Spencer Caraway and Lee Lewis in the win.
Massey added four boards, while Caraway pulled down five rebounds and notched four steals. Lewis added four boards and four steals to his total.
And as much as that helped Melbourne, so too, did the Bears' struggles to score after the first period. Mammoth Spring managed just four field goals and 10 points in the last three periods of play.
Derek Baird (six points) started things off with a bang for Melbourne by knocking down a trey in the game's opening seconds.
Seth Godwin (nine points), Wes Davis (four points) and Chris Young (five points) all hit buckets for Mammoth Spring in the first period, but the Katz closed strong with a triple from Massey and back-to-back hoops in the paint from Caraway to move in front 19-10 after one.
The Bearkatz added to this lead in the second with a 10-1 run midway through the stanza. Godwin hit the Bears' two hoops in the second and Young added a free throw, but Mammoth Spring was in a 31-16 hole at the half.
And that hole was just too much for the Bears to dig themselves out of, as the Bearkatz outscored Mammoth Spring 21-4 in the second half en route to a 52-20 victory.
Kody Caraway and Sam Cooper tallied two points each for Melbourne.
Caleb Brown ended the game with two points for the Bears.