When Russia Strikes Even After the Demise of Its Leaders... What Is the 'Dead Hand' Pointed Out by Medvedev

Amid the verbal battle between former Russian President Dmitry Medvedev and US President Donald Trump yesterday, Medvedev asked Trump to consider that Russia possesses nuclear capabilities dating back to the Soviet era, known as the 'Dead Hand.' What is this weapon? And how does it work?
Perimeter system, or Dead Hand, or as the West calls it, the Doomsday Machine, all names for a deadly weapon that can destroy any country at any time. It is a strategic automated system developed by the Soviet Union during the Cold War to ensure Russia's retaliation even after the leadership's demise, known as mutual destruction. It is still active in Russia's nuclear arsenal to this day.
This weapon aims to deliver a retaliatory nuclear strike against Russia's enemies even if the top leadership is eliminated and communication with military centers is lost, even in the darkest war conditions.
It has been redeveloped after the Soviet Union's dissolution to become one of the most destructive weapons in the world. How does it work?
Initially, the system is activated manually by orders from the top leadership. This does not mean it will launch but rather it remains in a state of readiness, only activated in the event of a nuclear war.
Then the system monitors a set of indicators such as seismic activity, radiation levels, and air pressure to detect any nuclear attack on Russian territory.
If nuclear activity is detected and communication with the leadership is lost, the system launches a missile called the Command Missile containing a wireless transmitter. The missile flies in Russia's skies and sends signals towards nuclear missile silos to launch independently on different trajectories, creating a simulation of Doomsday horrors for the enemy.