Also called as Skanda, Subrahmanya, Muruga; By virtue of being the senapati of the devas, he is identified as the god of war.
Peacock represents the excess ego and pride which is kept under control by Kartikeya.
Surapadman the son of Asura Vajranga and apsara Varangi grew up to be a terror to everyone including the demi-gods. The reason for his arrogance was the boon bestowed by Lord Shiva that none other than the son of the Lord himself will be able to take away Surapadman’s life. This was when Sati was no longer in Shiva’s life and Parvati was not yet married to Lord Shiva.
But unknown to Surpadman, Kartikeya or Subramanya, the six-headed God was born and was nursed to life by six celestial damsels. Kartikeya grew up to be the commander-in-chief of the Gods. Unable to bear Surapadman’s torture, the Gods approached Kartikeya to get them free from him.
A fierce battle ensued between Surapadman and Kartikeya, which eventually was won by Kartikeya. Surapadman, realised that his defeat was at the hands of none other than Lord Shiva’s son. Struck by Subramanya’s Vel, Surapadman asked for forgiveness and wanted to redeem himself, hence asked for forgiveness. Kartikeya forgave him and granted him the honour of being His vehicle or vahana, in the form of a peacock.