Revelations: Persona & Persona 2
Igor ( イゴール ), a servant of Philemon, is the proprietor of The Velvet Room, a room that exist between consciousness and unconsciousness. In Revelations: Persona, Persona 2: Innocent Sin, and Persona 2: Eternal Punishment Igor is shown with a phone made of bones which he uses to call the Personae from the depths of your soul. Igor is joined by three other servants of Philemon, Demon Artist, Nameless, and Belladonna.
Persona 3, Persona 3: FES & Persona 3 Portable
Persona 3 and Persona 3: FES
Unlike in previous Persona games, Igor never says anything about being a servant to Philemon, is no longer seen with his "Bone Phone", and is no longer joined by the three past residents; instead Igor is joined by Elizabeth. Instead of a room covered in blue velvet drapes, The Velvet Room is now seen as an elevator. Although at the end of Persona 3: FES everyone enters the Velvet Room, only the protagonist and Aegis can truly enter The Velvet Room at will.
Persona 3 Portable
Igor returns to The Velvet Room but this time he's joined by Theodore.
In Persona 4, Igor shows similar character traits as those shown in Persona 3 and FES and says nothing about being Philemon's servant. Igor is still the proprietor of The Velvet Room, but The Velvet Room has changed again from previous games. In Persona 4 The Velvet Room is now the interior of a limo driving through a foggy nebula. Igor is now accompanied by Margaret, Elizabeth's sister.
Persona 4 Arena
Igor makes only a brief appearance in Persona 4 Arena in a dream at the start of Yu's story mode, greeting him in the same manner as at the start of Yu's first trip to Inaba. However, he does not appear in any of Yu's subsequent trips to the Velvet Room; only Margaret is in attendance. The audio of his voice is actually comprised of reused lines from Persona 4. His Japanese voice actor, Isamu Tanonaka, passed away after the completion of Persona 4. Samples of his voice work were similarly used in the anime series Persona 4: The Animation.
Persona 4 Golden
Igor's role in Golden is unchanged from his appearance in the original version of Persona 4. Unlike other characters in the game, he has no new dialog, as once again all of Tanonaka's previously recorded lines were reused and no new lines were written for him. This is particularly noticeable in scenes where he is present in the Velvet Room with the all-new character Marie, as he does not acknowledge her presence in any meaningful way.
Igor returns to guide the new Protagonist on his journey. This time, however, he acts as the head of a prison, occasionally granting perks to assist the Protagonist with his "rehabilitation." Assisting him are the young twin prison wardens Caroline and Justine, who handle the bulk of the work of "executing" demons to fuse or strengthen them.
Igor now has a much deeper voice, as the original Japanese VA passed away after Persona 4 was finished. Later, it is revealed that Igor's very different voice is because the Igor that you interact with throughout the game is actually the evil god Yaldabaoth who took over the Velvet Room as part of a game to see if humanity still desired free will. The real Igor is sealed away until the twin assistants are fused into Lavenza and the fake Igor is exposed. From then on, the real Igor regains control of the Velvet Room, though Personas are still fused in the same way.