Jack is encountered in a “stalking” form for a few sections while the player is in the Main House. During these phases, Jack will either be aware or unaware of where the player is. Doing enough damage will cause him to collapse but he will rise again after a set amount of time.
Jack first becomes present in the Main House when the player walks past the Laundry room and down the hall. He will be unaware of where the player is and will go to the Dining Room.
Running into the Pantry after retrieving the hatch key will trigger an event where Jack will immediately enter and if gets close enough, will knock the player down and cut off their Leg leaving it detached, and taunt Ethan as he leaves a First Aid Med to give you a chance to survive. Unlocking the floor door and entering will despawn Jack.
Jack will be encountered as a boss fight when the player enters the garage. During this fight, he acts the same as stalking phase but at a certain point he will enter Ethan's car and use it against him. Once damage is done he will crash the car. Alternatively, if the players obtains the Car Key and uses it against him, an event will happen where Jack tears off the car roof and takes over the steering wheel and then crashes the car. After the car crash, Jack will emerge engulfed in flames and approach the player to attack for a set period of time until the car explodes which will end the fight with him.. Doing damage will cause him to flinch during this phase.
Jack will spawn in again during an event in Easy and Normal mode after the player picks up the Wooden Statuette and attempts to leave the bathroom. Jack will walk in at this point, prompting another fight-or-flight scenario. On Madhouse, Jack will spawn in in his unaware state when the player goes to the second floor, or will spawn and enter the Main Hall from the Ox Door if the player immediately picks up the Scorpion Key from the cage by the table.
Dropping down from the second floor to the first and then walking past the Laundry room will trigger an event where Jack smashes through the wall from the Pantry (leaving it open). This will also happen when you first get free from the dining room, lure Jack into the kitchen and then sprint down the hall to get the pantry room key.
Jack will not follow the player in the Sitting Room or anywhere in the Processing Area. He will despawn when you get the shotgun in the main hall.
He is encountered as a mandatory boss fight in the Morgue after the player picks up the Red Dog's Head. The adjacent hanging body bags in the arena can be kicked into Jack to stun him and provide the player a brief oppurtunity to attack, heal, or relocate.
After enough damage is done, Jack rips through the nearby fencing to pick up a scissor weapon, allowing Ethan to also pick up the Chainsaw. During this phase, head-to-head attacks while Jack is swinging the chainsaw often causes the attacks to cancel each other out. Once the player does enough damage per phase, his tumor-like weak spot will pop out, allowing Ethan an opportunity to use the thrust attack. Near the final phase, Jack knocks out the pillar in the middle of the room, limiting Ethan's maneuverability. Jack's torso will explode when he is defeated, rendering him unable to stalk and kill Ethan for the rest of the game until his return as a boss encounter in the Boat House.
After taking the Serums from Zoe in the Boathouse, an event where mutated Jack will grab Ethan and bring him into the open room and the fight will begin. Jack will mostly attack the player by smacking with his oversized arms. There are several orange nodules located on his face, body and limbs that must be destroyed to advance the fight. At some time when his face is damaged, he will vomit a liquid similar to that of the Fat Molded or even perform a grab attack.
After doing so much damage, an event will happen where Jack will dive under the water and pull Ethan over to the corner and the second phase will begin. Jack will raise his arms to smash down on Ethan repeatedly. In between his attacks, the player must damage his face to defeat him. Since damage will likely be received in this sequence, blocking is recommended to mitigate the damage from the overhead swings.
After stopping Jack in this phase, Zoe will open the door to tell Ethan to escape. Walking up to the exit will initiate a final phase where Jack grabs Ethan and the player will be promoted to use a Serum on him via button press.
Using the Serum will defeat him and end the fight. Not using it will make Jack instantly kill Ethan and result in a game over.
Jack appears in the "Banned Footage" DLC. In "Nightmare", he serves as the final boss, appearing in a variation of his second form from the main game (with chainsaw-scissors but not charred and wounded) and must be "killed" in order to complete the tape.
Jack is fought during the early hours in his first appearance form. He later appears in the final hours as a final boss in his Morgue form, carrying his giant shears.
Jack is first seen in the beginning, where he brings in Eveline due to finding her in the wreckage and brings her up to Lucas' old bedroom. Later on, Jack attempts to restrain Marguerite when she assaults her daughter and demands that Zoe get the rope from the garage, though when she does so, Jack then tries to attack Zoe and proceeds to self-multilate himself. If the player fails to bolt the door shut with the rope she carried earlier, Jack will ambush Zoe, with a Game Over sequence showing Jack and Marguerite dragging Zoe to "meet Eveline" with a "You Failed" message.
If the player attempts to escape via the garage, Jack will appear and forces Zoe out of the car and, angrily telling her that she's being rude for not meeting her 'sister', and proceeds to beat her while ranting that he won't stand for rudeness. It then shows a narration where it mentions that was just one resolution to Zoe's struggle and mention that the player failed to guide Zoe down the true way.
Ethan Must DieEdit
He also appears in "Ethan Must Die", in which he is killed by a turret off-screen to warn the player of the turrets in the house. His body lies in front of the first turret until the mode is completed.
End of Zoe Edit
His last appearance is within "End of Zoe", where he is seen as a swamp creature. He is encountered as a boss for the first time as his brother, Joe, treks through the swampy area after having found a place of safety for Zoe. After being beat down, he simply gets back up and leaves.
The next encounter with Jack is within a vessel that had been destroyed. This time, Jack grabs Joe and throws him all the way down to what appears to be the very bottom of the vessel. In this fight, Jack shows off his fighting capabilities and rushes at Joe with a barrage of punches, a double armed slam and even a grapple attack that cannot be blocked.
The final boss fight with Jack comes after he sent Joe into the swamp via a casket. He is found within the Main House once again, and appears after Joe tries to come to Zoe, and one last fight ensues. In this last fight, Jack is much more nimble than before and has a few new attacks via tendrils that he can spawn. These new attacks have long reach, can hit low, high or vertically, do exceptional damage and can be used consecutively. However, they can be blocked or dodged depending on what the player can do, though the latter is more dangerous since he can hit low.