Shoot the metal mask off a Panzer. Kill furies with knife / Dragon Shield melee or blasts. After each successful sequence, the Apothicon will roar. Return to Kino der Toten and check the mannequin ...

Make sure all the lights are activated and you’re ready to capture the Apothicon. Wait for the Apothicon to pass in front of the terminal, then activate it to shock the giant monster.