(Not to be confused with Not Grigori)
His appearance is that of Father Grigori from Half Life 2.
When entering the Dark room, there is a chance for Grigori to spawn in the far right corner of where you entered, illuminated under a spotlight and with his back to the player. Attempting to shoot him will deflect all damage and reflect it back to the attacker. If you attempt to get close to him, Grigori and the light prop will fade away after some brief flickering.
After initiating the event by pressing the button behind the credits billboard in the top floor of Building C, Grigori will spawn along with the several Combine, Antlion Guard, and explosive barrels. He is friendly to the player and will attack the Combine and Antlion Guard with his shotgun. They are likewise, hostile to him and will try to kill him. Due to his higher health pool, Grigori is more likely to outlive the Combine troops and may kill the Antlion Guard himself.
Freeing Sad Grigori
To free Sad Grigori from his curse you need to blow up the Dark room chair and obtain the Radio. Exploding the Darkroom Chair spawns the Ratman and will wander to his home in the Submarine Room. Once the Radio becomes avaliable, bring it to the Transmission hole in the far corner of the Ratman's Home and tune it until the portal radio music plays. You will know if you are successful if the music changes to the Half Life 2 "Distorted Trumpets" audio Shortly after the audio finishes, a voice will read out a series of numbers, "2796 1646 20." It is required for you to hear the full transmission otherwise the next step will not work. Once finished, the host of the server will have to type "2796-1646-20" into the developer console (the pauses in the reading of the code are represented as dashes in this instance). After inputting the command, you will be teleported to a corner in the Dark Room with Grigori. Three Fast Zombies will spawn in and Grigori will kill them. After this, he will say "Be aware" and then disappear.
- Freeing Sad Grigori is a non-repeatable event and he will permanently no longer appear unless you use the console command "gm13_reset yes" or replay the associated memories.
- It is unknown what becomes of Grigori after freeing him.
- Freeing Grigori is optional and is not necessary to unlock or complete the Notgrigori ritual.
- It is not known what the relationship is between him and Not Grigori, if there is any at all.
- While he will reflect damage from most weapons, it is possible to kill him with certain ones, such those that use the Entity Dissolver.