Bryan was knocked over by Brett's sudden attack, but he kept his wits about him. Brett was trying to clap a big hand over Bryan's mouth, and while Bryan's strength had been amplified by his father's muscles, their shrunken state had left him without enough raw strength to fight effectively.
His dexterity, however, was unaffected. So he quickly barked, "Back! Get back, Brett! And stay back!" Brett withdrew slowly, oddly. Like some kind of moonwalk, Bryan watched as his younger brother tried to struggle towards him, only to find himself backing up instead. From the expression in Brett's eyes, he had definitely gone off the deep end. Bryan realized there was only one way to be safe around such a violent person.
"Shrink yourself, Brett," Bryan said with a smile.
"No!" Brett howled, even as he rotated the wand in his hand. He clenched his jaw shut, but before too many moments had gone by, he heard the words come out of his mouth anyway: "I wish I was smaller."
Bryan watched as his brother cursed and spit, slowly deflating. After a few seconds, the shrinking seemed to stop. Only a few inches had been lost.
"You're going to have to do better than that," Bryan said, starting to feel his power. "Shrink yourself again, and by a lot this time."
Brett started to plead for his size, but before an entire sentence could get out, he heard himself say, "I wish I would shrink by a lot." Quickly, he shouted, "No, no, I don't wish that!" but it was too late.
The brothers regarded each other quietly this time, as Brett's size left him. The process moved along quickly, as Brett's clothes bunched up around him in every direction. Soon, his pants collapsed and his shirt became unmanageable. Bryan stepped closer as his brother was reduced to less than Bryan's current height. Finally, at about half of Bryan's size, the shrinking stopped.
Bryan stepped close to his younger brother, and looked down over his now hairy, muscular chest. He paused for a moment to rub the front of his new body, and stopped as he cupped his balls. "Damn!" Bryan said. "Dad sure has huge balls."
"Please..." Brett whimpered from below, unable to even complete his request. Bryan looked up from his crotch at the small form in front of him.
"You know, I could finish you off myself," Bryan said, "But it is so much more fun to watch you do it."