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This jutsu lets the user quickly switch places with another nearby object, such as a plant (normally a section of a log), an animal, or even another person within reach, the moment an attack hits. This creates an optical illusion, making the enemy think the attack was successful. The user can then use this confusion to escape or launch a counter-attack. Exploding tags can be attached to the replacement for an added surprise.
The anime has a number of other objects being used for this jutsu, such as a boulder, mud, a scarecrow, and even a large rolled-up carpet. These items are usually nowhere in sight, suggesting that they are merely gags meant to lighten up the situation and not an actual part of the jutsu. Additionally, the normal practice of switching places with a section of log is done in several places that have no such thing anywhere nearby.