Xintun

Xintun was a Herald of Unicron who served The Fallen.

Herald of Unicron
In 100,079 CMT, Xintun and his brother Xaaron were summoned by The Fallen to help him escape from the dimension he was imprisoned in when The Fallen needed to consume the energy of only one more being to escape. Xintun set about his task by attempting to trick the rogue Makuta Ynot into entering the dimension; when the initial attempt failed, he chased Ynot across several planets until he finally managed to lure him into the dimension. Ynot then placed a mask on Xintun that transformed him into a Hollow, which left Xaaron with no choice but to kill his brother by feeding him to The Fallen, thereby providing the energy that The Fallen needed to escape.

Although Blackout used the Vahi Cube to rewind time in the Original Universe by six months shortly after these events, Xintun remained deceased (presumably because his death occurred outside of the Original Universe).

Tournament of the Dead
In 150,080 CMT, Xintun was one of the many deceased characters who were resurrected by the Composer in the Underground to participate in the Tournament of the Dead, where he found himself standing next to three other formerly-dead beings: Helryx, Teridax, and Shattered Mirror Ynot. After the Composer informed the contestants that they would need to form Pacts by sorting themselves into pairs in order to participate in the tournament because those who did not would be returned to death, he bestowed a Pin upon Xintun that contained his life force and physical strength. Although all four of them could have survived by organizing themselves into two pairs, Teridax immediately tried to grab Helryx's Pin, which prompted her to floor him and take his in self-defence, killing him in the process. This left Xintun, Helryx, and SMY: an odd number. SMY decided that he would rather be paired with Helryx than Xintun, so he killed Xintun.