The geniuses are challenged to build a self-propelling boat using simple materials.

A paper-airplane engineering challenge is issued.

The geniuses try to prove their smarts by decoding Guy's gauntlet of pattern puzzles.

Terry and Guy battle the elements in Randy's big word challenge, and test their engineering skills in a bridge build-off.

Guy's battle of wits involves a helium-fueled race where it pays to be the slowest across the finish line, and a super-sized packing challenge.

Terry's battle of wits involves a mission to stack 100 lbs. on an egg without cracking, and an obstacle course for your memory.