An obstacle is defined as something that obstructs or hinders progress. . In the case of the Monster9 related content here on Sasukepedia, an obstacle is a part of a series of challenges in which competitors must complete in order to continue.
In the SASUKE tournaments, obstacles are meant to test a competitor's strength, speed, and stamina - effectively pushing their physical ability and mental will to their limits.
While similar to SASUKE, KUNOICHI obstacles however, focus more on balance and speed rather than strength and stamina.
In the VIKING tournaments, obstacles are meant to test a competitors strength, speed, and mental ability (such as a form of timed math or thinking).
In the Sportsman competitions, events replace obstacles, where competitors are pit against each other and they continue each event until only one competitor remains in the event.