Looking for a manhwa

Its an action manhwa full colored where he was a sword and was the sword of the greatest hero of all time who defeated the demon something then that hero became a king and the sword (mc) became an heirloom then fast forward to the future a chubby asshole prince was playing with the sword (mc) and accidentally stabbed himself with the sword so the prince died and the sword (mc) possesses the prince body and stuff.