If we say that the first challenge of hoop tossing largely relies on luck,
then this second challenge of sketch and guess has really little to do with luck.
Whether you can guess it or not entirely depends on how accurate the sketcher gesticulates, whether the guesser has a large enough idiomatic vocabulary, and the reaction speed of both participants.
Each idiom has only thirty seconds, the sketcher must decide quickly on how to gesture in order to help the partner guess the word as fast as possible.
But more importantly, the guesser must know the idiom. Otherwise, no matter how spot-on the sketcher's gestures are, the other party will not be able to give the correct answer.
During the last challenge, Lan Yu and Han Jing both agreed that the person tossing hoops was more important than the one directing positions.
The two decided who would toss the hoops with rock-paper-scissors.