|Specifics: This is for Crossing Over|
The Proton Pack/Realistic Version is an experimental and untested prototype upgrade of the standard Proton Pack, an unlicensed nuclear accelerator that functions by concentrating protons through the Neutrona Wand; its the Ghostbusters' main tool against negatively charged ectoplasmic entities.
The Proton Pack was a quantum leap in technology. It was the world's first energy-based weapon and the first and primary Ghostbuster tool against the supernatural, made by Dr. Egon Spengler and Dr. Ray Stantz in 1984.
For more information in the standard version, see Proton Pack
By Thanksgiving weekend in 1991, Egon Spengler and Ray Stantz completed the experimental Proton Pack with upgrades and secondary systems designed to enable them to be more flexible in the field and more effective against ghosts and other types of paranormal entities. These add-ons and upgrades include the redesigned Slime Blower, the powerful Composite Particle System and the experimental Dark Matter Generator. The upper right section of the pack was modified with several displays. One monitored the wearer's physical condition. The more green on the bar, the more damage the wearer could sustain and not get knocked down. The red bars monitored the pack's heat level. Before the bars rise to the top, the wearer should vent the pack. If the wearer does not, the pack temporarily shorts out and resets.  The Plasm Distribution System's plasm banks were integrated into the pack.  In addition, a new safety feature was integrated to the Proton Packs. When in use, the feature kept the Ghostbusters from accidentally crossing the streams. Protonic Feedback occurs and only causes the Ghostbusters involved to be knocked down by the backlash and suffer a bit of bodily harm. The safety can be turned off, allowing the packs to cross the streams in case of an emergency.
Just as Egon outfitted Ray with the pack, the Experimental Equipment Technician, Rookie, showed up for his first night of work. Egon wanted to start at 50% capacity to keep any burning or tissue damage to a minimum but Peter Venkman reminded him that the mortgage was in Ray's name. Peter suggested the Rookie. Egon revealed they perfected an extensive and rigorous training regimen to teach Rookie all of the pack's basic functions but they were interrupted when a Psi Energy Pulse moved through the Firehouse. Egon, Ray, and Rookie followed the newly escaped Slimer to the basement. Ray tried to talk Rookie through shooting Slimer but he accidentally blasted the Containment Unit and the Sloth Ghost was released. Ray and Rookie continued to pursue Slimer to the sub-basement but only recaptured the Sloth Ghost. When Peter questioned why the Rookie had the new pack, Ray reminded him it was packed with untested and extremely dangerous hardware with the capacity to blow him somewhere into New Jersey. As the night went on, Rookie got training on the fly as the Ghostbusters cleared up the Sedgewick Hotel then followed the Stay Puft Marshmallow Man through Times Square. In order to secure an alternate route through an alley, Egon waived precaution and activated the Boson Dart function on the experimental pack's Neutrona Wand.
The next day, the Ghostbusters were directed to the New York City Public Library. In the lobby, Egon and Ray activated the pack's Shock Blast and Stasis Stream functions of the Dark Matter Generator. As the trio moved further down the library in pursuit of the Library ghost, their path was blocked by a flow of Black Slime. Egon and Ray instructed Rookie on using the pack's Plasm Distribution System (PDS) to neutralize the slime. Forced to enter a cross-dimensional portal, they found themselves in a Gozerian dimension. Luckily, the packs were still functional. Ray quickly taught Rookie how to use the Slime Tether function from the PDS. That night, the World of Gozer gala was interrupted by The Chairman. As the Ghostbusters followed it down a secret passage, Ray decided to install a new Composite Particle System (CPS) into the pack. Ray taught him how to use the system's Meson Collider and Overload Pulse. In the final battle, in Central Park, the Rookie weakened Ivo Shandor's force field. Ray instructed everyone to get a capture stream on him, de-activate their pulse, then cross the streams with the blast function. They soon realized they were unable to shut down and were pulled through a portal where they battled Shandor again. As the Ghostbusters weakened Shandor's Supreme Destructor Form, Egon announced it was time to cross the streams again and deactivated the cross-stream governor.  Shandor was destroyed and the Ghostbusters were safely blown back into the physical plane.
Some time after the Shandor incident, the Rookie's experimental pack shorted out in Las Vegas, Nevada.  The experimental packs were deemed too dangerous to use anymore.  Egon eventually built a successor, the Boson Pack which could only generate Boson Darts. Rookie still used the experimental pack after he relocated to Chicago but only the Proton Stream function was still operational and a standard thrower was attached. 
The settings below are for the Proton Pack. As cases unfolded, Egon and Ray added and/or activated secondary systems to the Proton Pack, further increasing its effectiveness against more persistent and varied supernatural entities.
Using the Proton Pack's particle accelerator, the Neutrona Wand releases a concentrated stream of protons that fluctuates as it reaches a paranormal entity. The fluctuations of the Blast Stream tend to cause extensive property damage.
Name: Blast Stream Focusing
Upgrade: Reduces Beam Wandering
Desc: Utilizing a series of charged nucleon jackets, the Blast Stream Focuser increases the proton stream's stability, greatly reducing the amount of beam perturbation or 'wander'.
This increases your Proton Pack's accuracy.
Name: Blast Stream Recoil Decrease
Upgrade: Removes Movement Restrictions
Desc: Increasing the pack's number of nucleon jackets as well as adding a second proton buffer reduces the Proton Stream's negative energy kick back allowing the user to move more quickly while firing his weapons. Note: Smoking emitter coils are considered normal and should not cause concern.
This upgrade increases your mobility while firing the Proton Stream, allowing you to chase creatures on the move while maintaining maximum accuracy.
Boson Darts are super de-polarized bursts of extremely volatile, but very effective, boson particles. Boson particles quickly overheat the Proton pack so sparse usage is recommended. Accidental Neutrona Wand blockage could vaporize the surrounding 3 square miles.
Boson Darts are extremely effective bursts of protons that can quickly disperse big chunks of a target's PK energy. While this tool can be used in conjunction with the Proton Stream for a powerful one-two punch, the Boson Dart can also be used by itself to knock large enemies back or to disperse groups of smaller enemies. Use Boson Darts against small packs of creatures to inflict damage over a wider range or to blow off chunks of PK energy from moderately sized targets.
Effectively, Boson Darts behave like a grenade or rocket launcher: a slow-moving projectile which detonates on impact, dealing intense damage to anything in its immediate proximity. This applies to the corporeal and incorporeal alike. Boson Darts are effective for taking out groups of low-level manifestations with minimal effort, and can deal severe damage to more violent P.K.E. phenomena.
The Boson Dart was activated for the Rookie during the chase through Times Square, partly because of Egon's on-going field testing, but mostly in response to the Stay Puft Marshmallow Man and his lesser manifestations, the Marshmallow Minis. The Boson Dart was integral to the eventual defeat of the Stay Puft Marshmallow Man. Afterwards, the Boson Darts were added to the remaining Proton Packs, and the other Ghostbusters used them whenever they deem it necessary.
Name: Boson Dart Supercharge
Upgrade: Heat Cost Reduction and Damage Increase
Desc: It has been discovered that the addition of a fermion absorption ring to the Proton Pack's Neutrona Wand substantially reduces boson particle overheating allowing more Boson Darts to be fired before causing pack shutdown. Boson Dart impact damage is also increased. Also, accidental Neutrona Wand blockage vaporization damage is reduced to only 1 mile!
Of all Proton Pack upgrades, this Boson Dart upgrade is the best. Because the Boson Dart is extremely powerful, the ability to fire more Darts per charging cycle greatly increases your capacity to dish out damage in a short period of time. The increase in damage output is nice also.
Name: Boson Damage Immunity
Upgrade: User Damage Reduction
Desc: In addition to the installation of a secondary fermion absorption ring, extensive modifications to the Boson emitter's integrity field have led to the absorption of close range boson particles. This dramatically reduces the amount of damage taken by point-blank and close proximity Boson Dart impacts. Please note that these Z-based modifications in no way compromise the dart's Bose-Einstein statistics!
Because the Boson Dart is the perfect tool to disperse small groups of enemies like Crawlers, you're more likely to use it at close-range while they swarm around you. This upgrade allows you to more safely disperse Swarmers without the threat of taking blow-back damage from the Boson Dart's explosion.
The Capture Stream allows for the containment of ghosts. The Capture Stream can be used to contain Ghosts over a trap and to manipulate ethereal objects away from specters. Once contained in a Capture Stream, ghosts can be thrown against walls causing damage or even complete neutronization.
Even though the Capture Stream is an extension of the Proton Stream, it functions differently. After activating the Capture Stream, the rapidly fluctuating particles steady just enough to capture whatever they've surrounded, essentially creating a proton "cage" around the target. A pleasant side effect of the particles' steadying is that the Capture Stream is incapable of overheating your Proton Pack. Once a target is captured in the Stream, you can use it to wrangle the creature as it struggles to get loose, then slam it around to daze it. The Capture Stream can also be used on inanimate objects to solve environmental puzzles.
The Neutrona Wand will automatically switch to this setting when needed, but can also be manually-activated to move physical objects as well. The properties of the proton stream are altered so that the beam will coil and arc around its target, rather than blast it directly. With the proton stream on this setting, ghosts can be wrangled into a trap, and heavy objects can be moved out of the way.
The beam can also be 'pulsed' to forcibly bash ghosts against physical objects, further wearing them down. Ray has eloquently dubbed this technique 'Slamming'.
Dr. Spengler has not developed any upgrades for the Capture Stream.
Glenn Gamble worked on the Proton Pack. He was involved with the model, the HUD, the effects, the animated state changes, the upgrade states and the base weapon design. Since there was so much work done on it, the crew often referred to the pack as the "sixth Ghostbuster." In terms of the proton stream, Gamble and a programmer worked on its look and movement for a week. The hard part was getting the stream right from the player camera perspective and from the other Ghostbusters. For each iteration of the pack as it is upgraded, Gamble made sure the silhouette and color theme matched the new projectile so there would be no confusion on what configuration a player switched to. As the game became more action orientated, the crew realized the need for a HUD to convey information to the player. The HUD feature was born and from that point on, there would be at least 3 informational indicators on screen for the player. Gamble eventually added in statistic tracking elements and an interactive reticule so the player could spend more time looking at the game than the pack. Dan Aykroyd approved of Gamble's work on the pack. 
The Proton Pack's sounds were created in foley. Sound Designer Brian Fieser recorded a replica prop Proton Pack and jumpsuit for the Ghostbusters' movements in game. The recording was then layered with recordings of a backpack filled with random junk. The overheat sound was a combination of glass tubes, metal clangs, processed latches and steam hisses. The charging sound was remote control car servos layered with various sweeteners tuned to whatever the player is charging at the moment. Proton Stream variations and the turbo/slam sounds were created using various software synths. 
- According to Grant Gusler, the experimental Proton Pack was an advanced version Egon kinda worked on between movies. 
- The pack weighs 100 pounds. 
- The pack can function during a rain storm. However, functionality wasn't tested until the Ghostbusters proceeded through a section Central Park and battled the Cult of Gozer.  
- The Proton Pack was mentioned in Rookie's bio in the 30th Crossing Over Virtual Trading Card, released on May 31, 2018. 
- Ongoing Series
- Volume 1
- Volume 2
- Ghostbusters Annual 2018
- ↑ Ray Stantz (2009). Ghostbusters: The Video Game (Realistic Version)- Welcome to the Hotel Sedgewick Level "Searching Firehouse Sub-basement for Slimer with Ray" (2009) (PC/PS3/Xbox 360). Atari. Ray Stantz says: "Everything you need to know is displayed on the pack itself! Here's where you keep an eye on your current physical condition. The more green that's on the bar, the more damage you can sustain and still stay on your feet. This bar indicates your pack's heat level. When it gets to the top, you'll want to vent the pack and keep it from shorting out and resetting."
- ↑ Egon Spengler (2009). Ghostbusters: The Video Game (Realistic Version)- Checking Out the Library Level "Trying to follow Library Ghost after fighting Coal Golems" (2009) (PC/PS3/Xbox 360). Atari. Egon Spengler says: "This is the PDS: Plasm Distribution System. Basically, it's Slime Blower, Mark II, heavily modified from the earlier version. Your plasm banks are now integrated into the Proton Pack."
- ↑ GBTVGReferenceCrossingTheStreamsRV.jpg
- ↑ Egon Spengler (2011). IDW Comics- "Issue #3" (2011) (Comic p.12). Egon says: "Not the experimental pack our former associate used, it shorted out in Vegas."
- ↑ Tristan Jones post Ghostbusters Fans 5/10/12
- ↑ IDW Publishing Forums Erik Burnham reply 12/30/13 Erik Burnham says: "Just the proton stream. More work to make 'em, and the extra features aren't permanently stable as separate equipment is. Ray and Egon have been working on it."
- ↑ Glenn Gamble Weebly Portfolio
- ↑ Reddit AMA "AMA with the developers of 2009's Ghostbusters: The Video Game!" 7/16/16 Drew Haworth says: "The proton pack sounds were created in foley. Sound Designer Brian Fieser recorded an actual replica prop proton pack & jumpsuit for the Ghostbuster's movement. They layered that with recordings of a backpack filled with random junk. He knows at least an RC car was in there. The pack overheat was some glass tubes, metal clangs, processed latches, & steam hisses. The pack charging was some RC car servos layered with various sweeteners tuned to whatever you're charging at the time. The proton stream variations & turbo/slam were mostly created using various software synths."
- ↑ Reddit AMA "AMA with the developers of 2009's Ghostbusters: The Video Game!" 7/16/16 Grant Gosler says: "...this is not the original pack, but an advanced version. Egon kind of worked on the pack between movies."
- ↑ Ray Stantz (2009). Ghostbusters: The Video Game (Realistic Version)- Central Park Cemetery Level "Peter gives Rookie a boost over the front gate" (2009) (PC/PS3/Xbox 360). Atari. Ray Stantz says: "Junior's pretty spry, even with that hundred pounds of Proton Accelerator."
- ↑ Winston Zeddemore (2009). Ghostbusters: The Video Game (Realistic Version)- Central Park Cemetery Level "After Ray realizes Gozer is locked into one Destructor Form per dimension" (2009) (PC/PS3/Xbox 360). Atari. Winston Zeddemore says: "Hey! We ever test the Proton Packs in the rain?"
- ↑ Egon Spengler (2009). Ghostbusters: The Video Game (Realistic Version)- Central Park Cemetery Level "After Ray realizes Gozer is locked into one Destructor Form per dimension" (2009) (PC/PS3/Xbox 360). Atari. Egon Spengler says: "That's what the recruit is doing right now..."
- ↑ TomWaltz Tweet 5/31/18