Ulvar is a werebat, the weakest of the Seven Sons of Malar. There were supposed to only exist six Sons, but the leftover energy utilized for their creation led to his creation.
During the battle against a mysterious army of undead 5,000 years ago, he was defeated in battle and left for dead by Ulveric, who could not afford to waste energy in a crucial moment of the war.
He eventually became corrupted by a mysterious entity and became a hybrid between Vampirism and Lycantrophy, subsuming the consciousness of his original human host. He eventually was trapped and sealed by a group of Kelemvor’s followers in the Enclave of Kelemvor.
During the next 5000 years, he eventually spread his corruption throughout the Enclave of Kelemvor and twisted the servants of Kelemvor into bloodthirsty beasts. When the Seekers arrived in 1486 DR, they accidentally managed to free him by killing the corrupted keeper of the Enclave.
Connor Lycanmor entered the chamber where Ulvar was kept and he emerged as an elderly man, now adopting the name of Malik. When combat inevitably started, he drained the vitality of Zenvalros to regain his youth, fought and won against Connor’s primal bear transformation, due to the rapid regeneration of his wounds. He decided to spare his life because of Ulgyr’s request, and left the Enclave in his winged form, but not before recruiting Yinsaren, the only remaining survivor of the Enclave, to his cause.
Later in the Desert, after Ulgyr’s “death”, he showed his presence to Connor to show respect to his brother’s almost death, promising to kill him if Ulgyr somehow managed to die for real.