This article is about a monster. For the original human form, see Bertrum Piedmont.
"You may think I've gone... But I'm still here!"
Bertrum takes the form of a huge carnival "octopus" ride. He has four mechanical arms, with at least three carts per arm and four bolts (two per side) supporting his arms. The middle is in the decorative fashion of a carousel with his face, shouting, visible in the mid-section of the attraction. The arms, base and top of the ride are covered in theme park lights.
Inside the ride is Bertrum himself, appearing as a giant, disembodied, and slightly deformed human head with a large triangular nose, a paintbrush mustache, some scruff for a beard, bushy eyebrows, jet-black "hair" and bulged eyes with yellow irises staring in a dazed expression. There is ink oozing from the left side of his mouth, acting as either blood or saliva. He also has "veins" on his right eyebrow and on the left side of his forehead. He also has bumps on the left side of his head, near his ear. No matter what angle Henry faces him, Bertrum will always be facing towards him. He also has a small bald patch on the top of his head.
Bertrum only becomes hostile at the conclusion of his second audio log, with his face being revealed by two panels opening in the middle.
At the start of the fight, he will swing his arms rapidly both clockwise and counterclockwise, while slamming at least two of his arms down in an attempt to strike Henry. The first time he slams his arms, he slams the table with his audio log causing the audio log and the table to be destroyed while in the process, revealing an axe that can be used to defeat Bertrum. After a certain amount of time, he will charge up a hard slam with at least two of his arms, before pausing in order to recharge.
To defeat Bertrum, Henry must go to the table where the audio log once was to find the axe and avoid Bertrum's swinging arms by hugging close to the edges. There's a Bendy statue in the boss-fight room, so the player can't leave until he is defeated. Once Henry finds the axe, he must wait for Bertrum to do his slam attack and then strike at the bolts on whichever arms are made vulnerable. Henry has only a brief moment to strike these bolts, but with careful timing, he can hit at least two at a time. Once he eliminates all all four bolts on one arm, that arm breaks off. Bertrum becomes more hostile and gets faster each time he loses an arm. Henry must destroy all four arms in order to defeat Bertrum.
Alternatively, Henry can use a limited amount of weapon-based empty Bacon Soup cans (discovered later on after pulling the second power switch) to fight Bertrum, however it can be quite difficult to aim the bolts correctly without wasting any. When the boss battle begins, it is recommended not to pick up the axe while carrying the amount of cans, otherwise it will immediately cause all empty cans to drop, aborting a chance to trigger a later secret.
Also, when Bertrum slams down his arms, Henry can ride in the cars. This can be used for Henry's advantage when fighting.
He is located in the Attraction Storage room connected to Storage 9. Henry plays Bertrum's second last tape player on the table ahead from Bertrum's monster form. While Bertrum's tape log wrapping up his speech, his own monster form slowly activates and finally begins to attack Henry for a boss fight. During the battle, Henry manages to kill Bertrum by hitting all bolts from complete four arm cranes with the axe to destroy them, causing Bertrum to deactivate again and is overall destroyed. Henry can now activate the switch to power up the Haunted House.apartment; with one picture showing the Butcher Gang enemies riding in one of his seats, and the other of Ink Bendy coming out Bertrum's ride body where his face should be.
- The whole description of Bertrum's ride body is strongly modeled after a real-life amusement park ride; the Energy Storm. Even though, all ride seats connecting to the arm cranes rather resembles a mixture between roller coaster carts and carousel chariots.
- Even though his head model is used in the Archives chapter, his concept art is not seen anywhere but can be found in the game's page of Gavin McCarthy's website.
- Seen from Bertrum's head texture map file, there is no detail on Bertrum's left ear. Either it was an oversight or time constrain during development. However, from Pascal's video where he introduce Bertrum's head model turnaround preview, Bertrum still appears to have a texture for his other left ear.
- From Bertrum's ride body texture map, there is what seems to be an earlier version of Bertrum's face lacking shades that was located from the bottom left of the file. However because there is already a separated texture map for Bertrum's head, this face part from his body texture map file is completely unused.
- In the concept art by Gavin McCarthy, it appears that Bertrum's ride body would have been more disheveled than in its final appearance. For example, Bertrum's head would have been more exposed due to the panels exposing his face being partially busted open, most likely due to the fact that his head was there. His carts would have been more inky and dented, and several places on his body would have been cracked and splattered with ink.
Chapter 4: Colossal Wonders
- Killing Bertrum unlocks the "Around and Around" achievement.
- It's possible to get Henry riding on Bertrum's arms. Doing so will unlock the “Going to be Sick” achievement. However, this can happen only one time, and once the achievement is unlocked, Henry cannot ride on Bertrum's carts again later after starting a new game.
- If approaching close enough to either one of Bertrum's crane arms while in his deactivated state before starting the boss fight, Henry will receive minimal damage.