Tartarus seized power from Narcissus in a show of brute strength. After defeating Narcissus, he claimed the pack that had taken him in as a pup as his own.
As his name implies, he can cause an ungodly amount of hell to those that he deems unworthy of his time and efforts. He has no love for children and even will allow a breeding male to elope with his pack mates since he views rearing pups too much of a chore. His goal is simply to maintain his stranglehold over the pack by increasing their territory and forcing lone wolves to submit to his reign. Only males that show their strength are able to get close to him and ask for favors.
Tartarus's reign came to an end in surprisingly good circumstances. He grew the pack to over 100 adult members strong and had time to handpick his successor to the throne. Ghastly Design was a quiet, though fierce opponent that had challenged him and in one-to-one combat, he was defeated. Feeling that the pack was in good hands, he disappeared leaving Diomedes with his last litter of pups much to her heartbreak.