Object
Cyberman Chest Unit (with Deactivation Foam)
The chest unit of a Cyberman, which contains a critical deactivation foam system. When breached (e.g., by Toberman smashing it open), the foam spills out, immediately disabling the Cyberman and halting its attack. This event occurs during the cavern chaos in The Tomb of the Cybermen Part 4, where the Doctor, Jamie, Klieg's body, and Toberman witness the foam spill, turning the tide of the battle. The foam serves as a visual and narrative cue for the Cyberman's disablement, enabling the Doctor and Jamie to reactivate the cryostat and escape the reviving threat.
2 appearances
Purpose
Powers the Cyberman; breaching it causes foam leakage that disables the unit
Significance
Toberman's destruction of the chest unit kills the Cyberman mid-threat, buying time for Doctor and Jamie to freeze the tomb and exposing the machines' exploitable weakness amid Klieg's fatal hubris
Appearances in the Narrative
When this object appears and how it's used