Collect the secret poison used in Rioichi's famous knock-out sushi.
The Dragon Gates, which guarded the entrance to El Jefe's palace, were patrolled by several guards at all times. If the Cooper Gang was to gain access to the palace, they would need to get rid of the guards first. To do so, Bentley tasked Rioichi with collecting from the Sashimi Caverns two samples of the Spiky Wall Climber, which secreted a mild toxin that could act as a sedative. He warned Rioichi, however, not to be knocked out by the substance himself.
Rioichi then began collecting the samples while avoiding or dealing with Rat Henchmen and Mammoth Lighting Bugs. After he collected the needed amounts, he departed from the caverns.