Michael is between fifteen and seventeen years old, and he apparently suffers from rickets, an illness caused by vitamin D deficiency. It is unknown if this illness is the result of his demonic possession, neglect from his caretaker, or completely unrelated.
Michael's fate depends on the ending obtained by the player. In the "Murderer", "The Offering", and "The Hunter" endings, he does not reappear after his last encounter with the player, while in the "Father and Son" ending he kills John after emerging from the back seat of his car. For the "When Faith Endures" ending, Michael is shot by John and stumbles into the road where he is run over by a semi-truck. His mangled corpse is believed to be a Chupacabra.
Michael makes a brief appearance at the beginning of FAITH: Chapter II, revealing some of his backstory leading up to his appearance in Chapter I. Father Garcia, attempting to exorcise a demon from Michael, is shown to have restrained the boy in his basement. Eventually, the disfigured Michael escapes, kills and eats a random passerby, and jumps through a window, running off into the woods. It is assumed that Michael escaped to the woods surrounding The Martin House, where John encounters him.
The following quotes may be heard when Michael attempts to attack the player:
- "I HAVE THE BODY OF A PIG." (A reference to the Bible; Mark 5:11-13 details the story of Jesus committing an exorcism and the demons possessing pigs afterwards before drowning the pigs on the shore)
- "RUN! RUN! RUN!" (a reference to the game Sinistar)
- "WORSHIP ME!"
- "EN NOMBRE DE JESUS." (Spanish for "IN THE NAME OF JESUS," mocking a Christian prayer)
- "CORRUPTION, THOU ART MY FATHER." (a line spoken in the 2015 film The Witch, which got the phrase from the Book of Job, 17:14)
- "BLOOD!" (a reference to the Surgeon enemies from Shadowman)
When repelled by the crucifix or when shot during the 'When Faith Endures' ending, the following may play:
- "I GO UNWILLINGLY."
- "YOU KNOW NOTHING."
- "POR LA CRUZ INVERTIDA." (Spanish; "BY THE INVERTED CROSS.")
- "LA SANGRE DE PUTA MADRE." (Spanish; "BLOOD OF THE B*TCH MOTHER.")
- "QUE TE COJAN MIL CABRAS." (Spanish; "MAY YOU BE F*CKED BY A THOUSAND GOATS." roughly)
Faith chapter 2
- "I want to go home"
- "Can I see Mommy and Daddy?"
- "When they see what you did to me, THEY'LL KILL YOU"
- "YOU KNOW NOTHING PENDEJO"
- Michael's voice was made with the 1982 Software Automatic Mouth (or S.A.M.) program.
- In FAITH, when the player pauses the game while Michael is on screen the game will play a secret series of brief, rotoscope cutscenes.
- When Michael escapes from Father Garcia's basement in FAITH: Chapter II, the "3 months" photo will have strangely disappeared. This could possibly be the photo initially enclosed with Father Garcia's letter to Cardinal Gifford that was ultimately lost. What meaning this has, if any, is currently unknown.
- The line "I have the body of a pig" is a reference to an infamous EVP recording of a supposed "demon" that was proved to be fraudulent.
- The line "I go unwillingly" is based on a nightmare the developer had, where he was trapped with an "insane half-man half-rat" in a cage.
- In FAITH, the more times John repels Michael with the crucifix, the faster he attacks the player.
- The line "Que te cojan mil cabras" uses the verb cojer, which has several meanings across different Spanish speaking countries. The definition of cojer he uses is the one used in Mexico, meaning Michael Davies is most likely Mexican.