Y/N stood with Egon on top of the Shandor Mountain Mines. They were each wearing their old Ghostbusters uniforms with Egon also wearing a gray jacket over his. Y/N, now 58, sported his old proton pack. Age had clearly taken a tole of it with chipped paint and replacement parts dotted around the particle accelerator.
The two were looking up at the storm clouds above them. The clouds were swirling and an orange hue could be seen in the center. The two had prepared for this night. Gozer's minions were trying to return once more.
Y/N looked up at the storm clouds with anticipation. A strange light was starting to emanate from the center of it. When he looked closer, he saw a bright orb fly out from the light. It left behind a pink trail as it flew through the clouds. The orb slowly started to form horns and a dog like face. Y/N knew exactly what it was. The key master, Vinz Clortho.
Without a second thought, Y/N fired up into the clouds. His beam hit the storm cyclone, causing the dark clouds to spark with the energy of his proton stream. He readjusted his stream and caught the sentinel figure of the key master. It roared and tried to tug away from him.
While Y/N fought the demonic spirit, Spengler quickly threw out his ghost trap. Y/N was finally able to hold onto the tethered entity long enough to place it over the black box. Spengler hit the pedal and the trap doors opened. With a wine, Vinz Clortho was sucked down into the trap.
Just as Egon was moving to pick up the trap, Y/N heard a monstrous howl above him. He looked up and saw the figure of Zuul flying towards him. It was sooner than they expected. Y/N had to buy Egon time. He fired his proton stream at the beast, he hit it just enough to knock it off its trajectory.
Just then, Y/N's proton stream hit the center of the storm clouds. It started pulling on him like a fishing line. He tried to fight it, but he was slowly being lifted up towards the glowing portal. Spengler was about to try and help his friend, but Y/N turned to him and yelled.
Y/N: Go! Finish the job!
Egon hesitated for a moment before turning back and running away with the loaded ghost trap. Y/N continued to be pulled into the gateway. He couldn't shut his stream off as it tugged on him. With one last jolt of energy, Y/N L/N was pulled through the interdimensional portal.
Egon drove quickly away from the mines. He had stolen a company truck and was pushing the pedal down to the floor. The truck drove across the bridge and crashed through the locked gates, knocking them off their hinges. An invisible Zuul followed quickly behind.
Spengler continued driving the truck like a madman. He drifted past Spinner's Diner and flew down main street. He looked over at the burlap sack he was using to carry the trap. He lifted the sack to check the indicator light on the box. It was blinking a red light and letting out a dull beep.
With Egon distracted, Zuul took the chance to try and finish him. It smashed into the side door of the truck, denting it and causing Egon to lose control. Spengler drove off the side of the road and crashed through the cornfield. The truck flipped on its roof and came to a sudden stop.
Spengler managed to crawl out of the turned over truck. With the trap in hand, he ran through the field back to his rundown shack. He made it to the open dirt field and made sure to step over the raised mounds, careful not to hit the items buried in the dirt.
He hobbled over to his front porch and pulled up a large knife switch. Four large capacitators next to the field sparked to life as electrical energy flew between the large devices. The dirt in the field began to shake as the buried items turned on.
Egon waited patiently, waiting for his next catch. He held up the trap containing Vinz to tease its partner into coming closer. A faint light emanated from the closed box. Suddenly, large paw prints began to appear in the dirt as an invisible force was stepping closer.
Spengler lifted his foot above a metal pedal. He waited as the invisible terror dog stepped closer. When it was about halfway across the field, he quickly stepped down the pedal. However, things did not go according to plan.
The large capacitors sparked and died as the system was fried. All the items in the field lost their power. Egon continued to stomp down on the pedal, trying to get the system to work. Zuul saw its prey panic and began to walk closer, this time more quickly.
Left with no other option, Spengler quickly opened the door to his house and ran inside. He locked the door behind him and walked over to a wooden desk. He opened a drawer and rummaged through the contents inside, picking up his PKE meter. The meter's arms immediately came to live as the lights on them began to blink. There was a loud bang on the roof and the lights in the house flickered out.
Egon knelt down and carefully placed the ghost trap in a secret compartment hidden in the floor. He then placed a chair over it and sat down. Spengler looked at his PKE meter carefully, ready for his pursuer to strike.
Behind him, a billow of smoke blew down the chimney. It entered the room and covered the floor behind him. Through the smoke, Zuul took on a tall sentinel form. It began to creep closer to the man sitting in the chair.
Spengler looked down at his meter. The arms extended to their highest point and the light on the screen flickered wildly. The sentinel terror dog disappeared at seeing this. Egon had a feeling what was coming next. He pressed a button on the back of the meter. The arms flew up and a spark of electricity crackled between them as the meter entered taser mode.
Suddenly, monstrous arms ripped out of the chair. They grabbed a hold of Egon and tried to attack him. Spengler threw his arm back and hit one of the arms with the taser. Zuul howled out in pain from the assault. It lost its grasp and flew out of the house as a pink wisp.
However, the attack proved too much for Egon's old heart. His body gave out and collapsed in exhaustion. It laid there in the chair as the room fell silent. At that moment, Egon Spengler died.
The PKE meter fell under his chair during the attack. It laid under the place Egon spent his last moments defending. After a few moments, the lights on the meter began to blink as the arms slowly extended.