Similar to the Harley Heads, you will find all of the demon heads in a single location. That will be around the Wonder Tower area which includes the lairs of Ra’s al Ghul and Hugo Strange. This is a late-game location, so you need to reach the end of the main storyline before you can start exploring Wonder City.
Demon Seals have an orange glow in your Detective Mode, making it easier to spot them in the environment.
Since these seals blend perfectly with the environment, you might need a helping hand to find them all.
Where to find all Demon Seals in Batman: Arkham City?
There are a total of 12 Demon Seals to yank down in Wonder City. You can reveal their locations by interrogating Riddler’s green thugs which is a pretty exhausting ordeal. That is why we have marked all of the seal locations on the map below to make your achievement hunting easier.
Destroying three seals completes only one riddle, so all 12 seals complete four riddles in total.
Demon Seal #1 (Wonder Tower Foundations)
The first Demon Seal can be found above the elevator shaft of the Wonder Tower Foundations in Wonder City.
Demon Seal #2 (Wonder Tower Foundations)
This demon head can be found in the northwestern corner of the Wonder Tower Foundations area. From where you found the first Demon Seal simply drop down to the ground level and look under the staircase in the western corner to find the Demon Seal in Batman: Arkham City.
Demon Seal #3 (Wonder Tower Foundations)
Return back to the elevator shaft platform in the Wonder Tower Foundations and face the elevator shaft. Turn to your right to find the Demon Seal placed on top of the angel statue. Breaking the seal will complete one of the Riddler challenges.
Demon Seal #4 (Wonder Avenue)
Make your way to the Wonder Avenue of Wonder City through the Wonder Tower Foundations to find this demon head.
After entering Wonder Avenue, walk straight till you cross the second gate. The Demon Seal can be found placed above the second door.
Demon Seal #5 (Wonder Avenue)
This Demon Seal is quite hard to miss as it can be found placed on top of the door of Wonder Avenue that leads to the northern section of the area.
From where you find the previous seal, continue straight ahead until you reach the gate with a sign that reads ‘Wonder City’. It will be right above the gate.
Demon Seal #6 (Wonder Avenue)
This Demon Head is placed on the top of the door that reads ‘Temple of the Wonder City’ located in the North of the Wonder Avenue.
Simply walk straight from where you found Demon Seal 5 and you’ll find this Demon Seal hanging above the blue glowing light of the Temple’s door.
Demon Seal #7 (Chamber of the Demon)
The Demon Seal is placed on the entrance door of the Chamber of the Demon area which has been obstructed. To find a way to this Demon Seal, face the temple’s door and turn left to find a small opening.
Walk through that opening and take a right to the staircase that’s going below the floor level. Follow along the path to find a ladder that takes you to the entrance of the Chamber of the Demon. When you come up the ladder simply turn to your left to find the demon head.
Demon Seal #8 (Chamber of the Demon)
From where you found the last Demon Seal, simply walk straight to the Secret Corridor’s door located in far North of the Wonder City. Walk through the door to find this Demon Head placed on the right.
Demon Seal #9 (Chamber of the Demon)
This Demon Seal can be found on the left side of the door next to where Demon Seal 8 was in Batman: Arkham City.
Demon Seal #10 (Wonder Tower)
Return back to the elevator shaft in the Wonder Tower Foundations and use Batman’s Cryptographic Sequencer to unlock the elevator doors. Enter the elevator and use the Cryptographic Sequencer once again to make the elevator take you to the top of the Wonder Tower.
Once the Elevator has stopped at the top floor of the Wonder Tower, use your grappler to climb above the roof of the elevator where you’ll spot the Demon Seal. Take out your Batclaw and yank it off its place.
Demon Seal #11 (Wonder Tower)
Simply walk out of the elevator to reach the Observation Deck of the Wonder tower. Turn around to face the elevator and you’ll spot the Demon Seal on top of the arched doorway
Demon Seal #12 (Wonder Tower)
The last Demon Head will be placed on top of the Wonder Tower. To Ascend the tower, make your way across the tower towards the antenna by using the ledge on the East side. Once you’ve reached the antenna, take out your grappler and look up to find a small opening for Batman to grapple to.
Follow along the path to reach the central column of the tower. Jump across the column to find the Demon Seal placed above the entrance. Yank it off to complete the Riddler Challenge.