Well it seems like Gaara was on the defense against the Mizukage at first.[
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] His oil based attacks were destroying his absolute defense (possibly a good counter to them) and his team was clearly on the losing side. Later on, Gaara decided to use the knowledge that the Mizukage provided him and searched to find the clam causing the battlefield wide genjutsu instead of attacking the mirage itself.[
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] After finding it using his sensory sand, Onoki took the spot and decided to destroy it. He wanted to use Jinton to abolish it at first, but was forced to use his rock fist technique instead since he was running low on chakra. [
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] This did not have enough strength to break the clam apart, so he had to further increase the strength of it by putting more strain on himself.[
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] This did the job. However the strain took out his weak back and he was left defenseless against the Mizukage.[
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] Gaara saved him by substituting the real Onoki with a sand clone to fool the enemy. This was effective because once he "killed" the sand clone, the sand it was made up of took him by surprised and was able to trap the Mizukage in a layer of sand. The Mizukage then realized that Gaara must have been watching the entire thing closely with his third eye.[
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][
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] Gaara then trapped the Mizukage in a sand pyramid, taking away his movement as they sealed him.[
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] They thought this was their win, until the Mizukage ultimately pulled out his trump card: Jokey Boy (which completely destroyed the pyramid in the process).[
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]
I was gonna type the second part but since they're not available on the Narutobase I cbf trying to look it up from another site xD. Basically, Onoki explains to Gaara that Jokey Boy takes in heat by running around the battlefield, and starts expanding until it gets to a certain point in which it gives a powerful explosion. This deflates the clone back to normal size and the process begins all over again (which is why it's called the infinite explosion technique as well). Trying to subdue it, Gaara sends small waves of sand at it but to no avail because of its extreme speed. Onoki says that it's much more preferable to search for the real body (which Onoki claims would be weaker after using this jutsu) than to fight off Jokey Boy. The Mizukage curses Onoki for knowing so much, and an Alliance member quickly senses the location of his real body. Onoki's back is still broken, so he's pretty useless in this fight other then for knowledge(going as far as saying that he can't move at all). Gaara follows the sensor's wishes and finds the real Mizukage, trapping him once again in a sand pyramid. Right before the sealing squad finishes the job, Jokey Boy (now the size of the pyramid itself) quickly takes away all the sealing tags from the pyramid's surface.
Now the Mizukage decides not to help them anymore, and wishes for them to figure it out on their own. His body now uses the pyramid as a hiding place (being able to move about it freely because of his oil body). Soon afterwards, Jokey Boy explodes and releases a huge explosion. Gaara saves the alliance using an impressive wall of sand in the shape of his mother. However, it's well known that the jutsu isn't going to stop until Gaara thinks of a solution to it. Jokey Boy then makes a weapon out of its arm, and jumps on the waves of sand attacking him to reach Gaara himself. Gaara tried defending himself, but was too slow because of the Jokey Boy's sudden expansion (making itself larger right in front of Gaara). It turns out that Gaara was actually a sand clone instead, and the remains of the clone covers Jokey Boy (Gaara having predicted this all along). The Mizukage is surprised that Gaara's sand is now able to catch up to Jokey Boy, and even more surprised when he sees that Jokey Boy is unable to explode. Gaara explains that the sand clone was actually made up of gold dust, which covered Jokey Boy thus weighting him down. The heat that Jokey Boy gave off melted the gold into Jokey Boy himself, stopping the jutsu by totally restricting the clone itself. The gold acted as a conductor, and Jokey Boy didn't have the heat it needed to explode. The Mizukage then gets sealed in the pyramid, thus ending the battle.
