First Crota Fireteam
From Destinypedia, the Destiny wiki
The First Crota Fireteam (also known as Eris' Fireteam) was a Guardian Fireteam composed of six Guardians: the Warlocks Toland, the Shattered, and Eriana-3, Hunters Eris Morn, Omar Agah, and Sai Mota, and the lone Titan Vell Tarlowe. Together they ventured deep into the Hellmouth, in an attempt to assassinate the Hive god Crota. They ultimately failed, leading to the deaths of all but Eris, who lost her eyes and her Ghost during their quest. Years later, it would be revealed on two separate occasions that two others had also survived, unbeknownst to Eris, and were encountered by chance in the travels of the Guardian.
Eriana-3, a survivor of The Great Disaster, sought a means to bring an end to the Hive god Crota, who had slain the Warlock's girlfriend Wei Ning during the ill fated campaign. Along with Eris Morn, she searched for means to exact her revenge, with little success. Their search found them a possible answer in an unlikely man: Toland, the Shattered. The exiled Warlock had insights into the Hive that convinced Eriana enough to recruit Sai Mota, Omar Agah, and Vell Tarlowe, and make an attempt on the Hive's fortress to kill a god.
The Fireteam camped out at the moon base in the Anchor of Light, planning their assault.. The six made for the Temple of Crota, where they were confronted by Alak-Hul and his consort Verok. Tarlowe, undaunted by the foes, charged in but was overwhelmed by their spawn of Thralls and fell.
The remaining five managed to enter the Hellmouth, and followed the screams of Omnigul deeper into the Hive stronghold. Somehow, the team was split up, with Eriana-3 and Sai in one group, and Toland, Omar and Eris in the other. Toland slipped away at some point, seeking out Ir Yût, the Deathsinger, wishing to learn the secrets of her Deathsong, in which he was interested. The Song killed him, detaching his soul from his body and sending it to the Ascendant Plane. Eriana heard his screams echo through the Hellmouth.
The rest of the group fell in short order. An injured and near death Omar was captured by the Heart of Crota, his Light stripped from him to feed unborn Hive, and succumbed to the torture before Eris's eyes, however unbeknownst to everyone, the ritual went awry allowing Omar to survive. Sai, fighting with the bones of fallen Acolytes, was killed by Omnigul herself while trying to escape from the Hive. Eriana made it to the very bottom of the Hellmouth, sending off her dying Ghost Jax, remorseful for her foolish quest and the death she caused, fighting the Hive with what remained of her Light. Toland saw her from the Netherworld, and believed her to have been brave in her final moments.
Eris survived, losing her eyes and her Ghost Brya, hiding in the dark tunnels of the Hive. She clung to a copy of Toland's Journal, learning from it of the dark secrets of the Hive the Warlock had discovered.  It is also likely that an Ahamkara bone aided her in finding her way out. Long after, she would emerge from the pit, changed after years in the dark. Seeking vengeance for her friends, she would guide Guardians to fight against the Hive on her behalf, ultimately leading to the death of Crota and the rest of the Hive who she deemed responsible for the horrors in the pit.
While Eris herself believed to be the only survivor of the fireteam's fatal strike, it later turned out three out of six team members survived in some form. Apart from her and Toland, Omar was also found alive as a Hive bug trapped in a crystal, after the Heart of Crota had accidentally stripped not only his Light from him, but also his soul. The Guardian later found him deep within the Tunnels of Despair and brought to Eris, who put him into his treasured machine gun Xenophage.
Rise of Nightmares
Upon discovering the Pyramid deep under the Moon's surface, Nightmares of her old fireteam members began to haunt Eris in order to deter her from her quest against the Darkness. The longer she and the Guardian worked to find a way into the Pyramid, the more phantoms appeared to taunt her - even Toland's, whom Eris already knew had survived. The Guardian aided her by finding lost keepsakes of her friends and bringing them to her to invoke the real memories she had of them, aside from the pain and grief. Eris kept the memorabilia to remind her of who they truly were, and that allowed the phantoms haunting her to disperse.
Throughout the Hellmouth, several dead Ghosts can be found, which, upon finding, play snippets of their final transmissions. Some of these Ghosts belonged to the First Crota Fireteam: Sai's Ghost Yuka, Eris' Ghost Brya, Toland's Ghost Guren, Omar's Ghost Karsys, Eriana's Ghost Jax and Vell's Ghost Razor. Before the Beyond Light update, finding them unlocked entries in the Luna's Lostlorebook that, apart from the transcripts of the transmissions, give more information on how the fireteam members joined the group, and various interactions between them.
List of appearances