The Helix Stone is an artifact from Hell found in Doom (2016). It was retrieved from Hell by the UAC in one of the Tethering Operations, and is credited by Dr. Samuel Hayden with revealing the secrets of Argent energy, as well as containing information about the Doom Slayer, including his ultimate fate and location within the Kadingir Sanctum. He states that Olivia Pierce was completely obsessed with the artifact and had spent years studying it. As such, it is found within her personal private office within the depths of the Lazarus Labs.
The Helix Stone can be seen several times in the violent psychic visions experienced by the Doom marine during travel between different areas and when coming into contact with other items involved in his history, such as the Praetor suit. It is finally encountered when the marine enters the Lazarus Labs, at which point the Stone shows him the location of the Crucible within the Necropolis. Through some unknown mechanism, Dr. Hayden and VEGA are also able to sense or otherwise detect the information which is revealed to the marine. Hayden claims that it is the Crucible that Olivia was after all along, and sends the marine on a quest to return to Hell and retrieve it. VEGA quickly determines that this necessitates facing the cyberdemon, as the Argent accumulator it carries contains the only sufficient concentration of energy left to open an accessible rift.