The Rebels (20-2, 14-0) held a 44-25 halftime lead and shattered any hopes of a Catoctin comeback with an 11-2 run to open the third quarter and a 9-0 run to close it for a 71-31 lead.
"Obviously they are a more talented team than us, but we had a lot of turnovers and that didn't give us much of a shot," Cougars coach Ryan Oman said.
Catoctin (7-15, 5-9) never led, but managed to slow the Rebels early, playing to a 6-6 tie midway through the first quarter.
But it was short-lived as South moved back on track as it reeled off nine straight points - highlighted by a monstrous one-handed slam by Miner to ignite the Rebels' home crowd.
"I was trying to dish the ball to some of my teammates, but I got some good looks and took them," said Miner. "We played a good game and it's going to give us some confidence going into the playoffs."
Miner finished with a game-high 29 points, giving him 1,683 for his career and leaving him just 81 points shy of Colby Bachtell's boys' county mark (1,764).
"I don't even think about that record when I'm playing," said Miner. "If it comes, then it comes, but I'm not worried about it. We need to focus on winning."
Wayne Young chipped in 11 points - all coming in the second half - and Jesse Gutekunst added 10 for the Rebels, who will ride their momentum into the Maryland Class 2A playoffs.
"They're going to be tough to beat," said Oman. "This game was good for us because it showed some things that need a little more work and we'll try to fix them in time for the playoffs."
The Cougars host Smithsburg in the first round of the Class 1A West playoffs Saturday at 7 p.m.