When an entrepreneur brings in a new recreational sport to the tank, the sharks get a chance to suit up and ram into each other with reckless abandon; two brothers designed a fashion brand enabling the wearer to do good while looking good; and a couple have a solution to the mystery of the missing sock. Also, an update on Mensch On A Bench that Lori Greiner and Robert Herjavec invested in during Season 6.

A Christmas-decorating aficionado has a high-tech way to deck the halls with animated glow balls and synchronized musical trees; an entrepreneur has whimsical knit hats, complete with detachable facemask; two Harvard grads have a line of ornate, pop-up greeting cards for all occasions; and two women demonstrate their all-natural deodorant made from activated charcoal. Plus, Daymond John gives a workshop to the principals of four of his companies — Bombas Socks, Sunstaches, Myself Belts, and Cozy Bugs — and brings out chef Rocco DiSpirito to provide some delicious inspiration.