The visions shown to the Thunder God were sent by Raiden to his past self, in order to prevent Armageddon during Mortal Kombat (2011). Raiden had failed to stop Shao Kahn from obtaining the power of the fire elemental Blaze, and as such, stood poised to finally conquer and merge all realms to Outworld. With his final moments, Raiden gathered the remains of his amulet and used it as a focal point for a spell to send visions of events that had already occurred, along with a single cryptic message: "He must win".
The Raiden of the far past received the visions at the tenth Mortal Kombat tournament on Shang Tsung's Island, and at first interpreted the message to mean his chosen champion, Liu Kang, to the one who must win against Shang Tsung. Raiden also attempted to prevent the death of the Elder Sub-Zero, Bi-Han, at the hands of the vengeful wraith Scorpion, so that the evil Noob Saibot may never come to be, but Quan Chi's manipulations saw this event come to pass as it had before.
Raiden would receive more visions in the Outworld tournament, and took active measures to prevent the Lin Kuei ninja, Smoke, from becoming one of the cyberized Lin Kuei cyborgs. This had the unfortunate backlash of seeing the younger Sub-Zero, Kuai Liang, captured and turned in his place, with the Lin Kuei likewise swearing fealty to Shao Kahn, bolstering his forces.
During Shao Kahn's invasion of Earthrealm, Raiden continued to receive visions to his frustrations, at a loss to understand the meaning of his future self's message. Though he was able to save the life of Johnny Cage from death at Motaro's hands, this act spurred Shao Kahn to empower the revived Sindel with the countless souls Shang Tsung had consumed, killing the sorcerer, and giving Sindel the means to single-handedly nearly wipe out all of Raiden's chosen champions, whose souls were claimed by Quan Chi and revived as undead revenant slaves for the Netherrealm.
Raiden soon realized the true meaning of his future self's message: That he must allow Shao Kahn to attempt his merger of Earthrealm and Outworld, in clear defiance of the Elder God's decree that realms could only be merged by winning Mortal Kombat, to invoke their wrath and destroy him once and for all. Liu Kang by this point had believed Raiden to have simply gone mad, and attempted to face Shao Kahn again against Raiden's wishes, which resulted in his accidental death at Raiden's hands.
As Shao Kahn boasted of his victory and pummeled Raiden to an inch of his life, the visions of the future melded with the present as Shao Kahn prepared to kill the thunder god with his Wrath Hammer, only for the Elder Gods to finally intervene and empower Raiden with their might. Shao Kahn was defeated by Raiden, and destroyed by the Elder Gods, which prevented Raiden's visions of Armageddon coming to pass.
After these events, the visions of the future no longer came to Raiden, but over a decade after Shinnok's failed invasion of Earthrealm, Raiden would use the Kamidogu dagger of Orderrealm to invoke Blood Magik in an attempt to gain insight on the demon lurking about between Earthrealm and Outworld, though the attempt besieged Raiden of visions of many kombatants across both realms instead.
During Shinnok's second invasion of the Sky Temple to claim Earthrealm's Jinsei, the vengeful revenant of Liu Kang would mockingly ask if Raiden still received visions of the future before bitterly reminding the thunder god of his actions that resulted in his fall from grace.
In the final hours of the time crisis besieging the realms, Raiden's past self would once again receive new visions as he became corrupted from using the Amulet of Shinnok, with Liu Kang once more preparing to battle the maddened thunder god as he would have in their past. This action stopped Raiden and his corruption, the thunder god coming to a sudden realization, which would fully unlock the visions full patterns, revealing that Kronika had been manipulating entire events in every timeline for her endless war to ensure he and Liu Kang would come to blows, with Raiden killing him to keep them separated as only their combined power was a threat to her designs of balance.