Tripura: Three cities of Asura's

 According to the legends, Once there was a Demon King Tarkasura whose reign was terrifying for the common people as well as gods.He was killed by Lord Kartikeya as Tarkasura  had a boon that he would only be killed by  Lord Shiva's son. Tarkasura  had three sons- Tarakaksha, Vidyunmali and Kamalaksha. After death of their father, they were saved and brought up their Uncle Mayasura . 

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   Mayasura was devotee of Lord Shiva and he was an great architect, he made them( son's of Tarkasura) to worship Lord Shiva from their childhood and they became devotees of Lord Shiva. When they entered in their manhood, Mayasura told them to do penance of  the creator of this world- Lord Brahma to seek boon for welfare of the Asura's. 

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  They did severe penance of Lord Brahma and made him happy. Lord Brahma appeared in front of them and told them to ask for boon. They were delighted to see Lord Brahma in front of them and they asked for immortality like the other Demons wanted who do penance of Trimurti ( LORD BRAHMA, LORD VISHNU & LORD MAHADEV ).

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  Lord Brahma told them that no one is immortal in this world who has taken birth on this earth, you have to ask for something else. They then asked for the three puras or fortresses which will not be won and destructed by anyone and anything. On this Lord Brahma again told them that nothing is permanent in this world. 

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    So they cleverly asked Lord Brahma to give boon of the impregnable fortresses which will only be destructed by Lord Shiva when the fortresses will be in one line. Lord Brahma given them that boon and got vanished. They were devotees of Lord Shiva so they considered that Lord Shiva will not do any harm to them. So they considered themselves as invincible. 

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     Then after that, they went to there uncle Mayasura- the great architect of Demons and he created the three fortresses. The first was made with iron walls in pataal, the second fortress was made with silver walls and third one was made with gold walls whose king was Tarkaksha.

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  Due to the boon of Lord Brahma the fortresses were safe and prosperous. Mayasura after creating the fortresses again went for his penance of Lord Shiva. In tripura, Mayasura created a magical pond which had magical powers which can heal and can bring a dead one to life. Mayasura also made confirm that the three fortresses would never come in same line. But everything has a lose point, at a certain time of year they come in same line. Tripura became home for the Asura's.

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     The asura's were happy there for years but due to their demonic nature they again started creating chaos in world and attacking Dev's and sages. Due to their attacks, Dev's went to Lord Brahma and Lord Vishnu for solution. They both said that due to boon only Lord Shiva can save them from demons.

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   They went to kailash to meet Lord Shiva and told him their request. On this Lord Shiva gave assurance that Asura's can't harm you as I am sending Nandi with you . Then in a battle with Asura's Nandi killed Vidyunmali and many soldiers of Asura Army. They started losing the battle against Dev's and ran again in their fortress where they were safe from anyone. 

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   Mayasura again given life to Vidyunmali by submerging him in the magical pond. After this three brother's again went in battle and Dev Soldiers were in terror to see Vidyunmali in battle again. They came up with more power and started killing Dev Soldiers and they also injured Nandi in that battle. On this Lord Shiva got angry on the Asura's. 

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   And when the time in which the the three puras were in same line was near, Lord Shiva ordered the chariot on which he can destroyer the three puras and the Asura's. So Devi Prithvi ( earth)  became the body of the chariot and sun and moon god became the wheels. Lord Brahma became the charioteer. Mount meru became the bow and Vasuki became bowstring.

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   Lord Vishnu's Sudarshan Chakra became arrow of the bow while Agni Dev and and Vayu Dev were present at the front and back end of arrow. All other gods done the same thing  as they were also present with Lord Shiva in any other form which would be beneficial for destroying the Tripura.

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    When the three fortresses or tripura came in alignment in single line, Lord Shiva shot the arrow and realised that Mayasura his devotee was inside Tripura. Nandi hearing Lord Shiva's Inner voice went faster than arrow and informed Mayasura to leave Tripura as it was going to destroyed. So he flew away from there and his one of the greatest creation was being destroyed due to the bad and horrible acts of Asura's.