Why is Lord Shiva identified as Mahadeva?
Such a thing is clarified in Karna Parva, in a conversation between Duryodhana and Shalya about the latter being the charioteer of Karna, in the process Duryodhana narrates the destruction of Tripura:
Duryodhana said, 'O supreme among kings! The gods accepted what the lord of the gods had said. 324 All of them gave him half of their energy and he became superior. The god became the strongest among all the strong ones. From that time, Shankara came to be known as Mahadeva.
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