Description: A cortical stack is a tiny cyberware data storage unit protected within a synthdiamond case the size of a grape, implanted at the base of the skull where the brain stem and spinal cord connect. It contains a digital backup of that character’s ego.
Part Nanoware, the implant maintains a network of nanobots that monitor synaptic connections and brain architecture, noting any changes and updating the ego backup in real time, right up to the moment of death. The average transhuman’s cortical stack backs up their ego 86,400 times per day. Only the most recent backup is kept within the stack; older ones are overwritten. Pods and synthmorphs also can be equipped with cortical stacks (though AI-piloted bots often lack this feature), though these versions maintain an updated copy of the ego running in the morph’s Cyberbrain. If the character dies, the cortical stack can be recovered and they may be restored from the backup.
Cortical stacks do not have external or wireless access (for security), they must be surgically removed. Cortical stacks are extremely durable, requiring special effort to damage or destroy. They are commonly recovered from bodies that have otherwise been pulped or mangled. Cortical stacks are intentionally isolated from mesh inserts and other implants, as a security measure to prevent hacking or external tampering.
High rollers, well-equipped Brinkers, and others in dangerous professions often opt for an Emergency Farcaster accessory that periodically (usually every 48 hours, but varying according to contract) transmits a backup from the cortical stack to a remote storage facility. This option is quite expensive, however, and so is generally only afforded by the wealthy.
Retrieving A Cortical Stack
Most cortical stacks are carefully excised from a corpse with surgery. In certain circumstances, however, a character may need to extract a cortical stack in the field, whether because transporting the corpse is impractical or because the dead person is an enemy and they either don’t want them knowing who killed them or they want to interrogate them with psychosurgery in a simulspace.
The process of cutting out a cortical stack is called “popping,” as a skilled extractor can usually get the smooth-shelled implant to pop right out by making an incision in the correct place and applying pressure. One does need to be careful that the tiny, blood-slick stack doesn’t slip away once popped. Popping can be done with a sharp knife and elbow grease, though it is grisly. Popping a stack is a Task Action that requires a Medicine: [any appropriate field] Test with a timeframe of 1 minute and a modifier of +20. Morphs with stacks in non-standard locations or with anatomical shielding (carapace plates, etc.) around the stack may incur penalties to this test at the gamemaster’s discretion. Of course, if you don’t have the time for a precise extraction, you can always just cut the entire head off and take it with you.
Cortical stacks may be excised from living people, but the process is usually fatal (or at least paralyzing) as it involves cutting through the spinal column. If the target is not unconscious or otherwise incapacitated, they must first be immobilized in melee combat. Cutting out the stack is handled like a Medicine Task Action as above, but this process inflicts 3d10 + 10 damage on the target. If the test fails, they still inflict 1d10 + 10 damage to the target. If the person removing the stack wants to leave the target alive or harm them as little as possible, they suffer a –20 modifier on the test, but may reduce the damage by 1d10 per 10 full points of MoS. Living through the process of having your stack removed is traumatic; anyone who does so suffers 1d10 mental stress.
Once a cortical stack is retrieved, it may be loaded into an Ego Bridge and used to bring the ego back, either as an Infomorph or by Resleeving.
Cortical stacks have an Armor of 20 and a Durability of 20 for anyone attempting to destroy them.