Fort Apocalypse is a game developed by Synapse Software and released for the C64 in 1982. The war with the Kralthans is on, and they've taken prisoners. These people must be rescued from the Draconis caves and the Crystaline caves that are located just outside the titular Kralthan main command center. The Fort is too powerful to attack directly, but perhaps a single rocket copter, carefully controlled, might be able to do what an army cannot. However the caves are narrow and the enemy has still setup impact shields, defenses and Hyper-Chambers within their depths.

nymx rescues all of the humans trapped in the fortress, destroys the reactor core there and makes his way back up in record time.

FLASHING LIGHTS WARNING: The destruction of the core at 1:47 in the encode produces flashing lights for about 3 seconds that may cause epileptic seizures.

A documentary about this TAS can be viewed here.