The Universal Solvent is a 1995 comic created by Don Rosa, and originally published in the Danish Anders And Co (first U.S publication Walt Disney Comics And Stories in 1996). Based on a story Rosa wrote for his comic strip The Pertwillaby Papers called Vortex, The Universal Solvent also served as a semi-sequel to Carl Barks story Land Beneath The Ground, and would eventually be followed by one of Rosa's most popular Scrooge McDuck stories; The Black Knight.
It's another regular day in Duckburg as Scrooge McDuck drops by Gyro Gearloose's gadget shop to check in on a project he's commissioned from the inventor. Scrooge's mining companies have tapped out most of the mineral wealth close to the surface of Earth, he's in the market for something that would make it easier to dig deeper in the Earth's crust, and as usual, Gyro has delivered in spades - the Universal Solvent (also called the Omnisolve), a revolutionary substance that can instantly dissolve any matter, no matter how tough or durable, with the sole exception being diamond, which is also used to contain the Solvent, or coat other items with it.
Unfortunately, Scrooge's unveiling of his new product goes poorly, as the assembled reporters scoff at the entire concept, thinking it's some sort of bizarre scam. A frustrated Scrooge pours the Omnisolve out on the ground to demonstrate it, much to Gyro's horror, as he only now realizes Scrooge didn't understand just how dangerous the Solvent actually is; Scrooge has effectively doomed the entire planet with his careless action, as the Omnisolve will simply eat its way straight down to the Earth's core, destroy the planet's magnetic field, and eventually cause the planet itself to begin to tear itself apart as gravity goes haywire. Thankfully, an airtight seal is formed over the shaft created by the Omnisolve when a billboard is sucked on top of it by the vacuum formed by the Solvent digging it's way into the Earth, giving the Ducks a small chance to retrieve the Solvent and save the world before all is lost.
Building an air lock above the shaft to prevent oxygen from rushing down and crushing anyone trying to venture down into it, Gyro also cobbles together a motorized platform and several "space" suits to allow the Ducks a chance to survive their dangerous mission. The journey is long and difficult, especially as the Ducks can't even remove their helmets to eat or drink until they reach the initial level of oxygen that followed the Solvent, though they also get to witness a section of the shaft where the walls are covered in diamonds, the only parts of the planet the Omnisolve can't affect. Hours pass, and the Ducks eventually find themselves not only able to breathe and eat again, but also becoming increasingly weightless the closer they get to the Earth's core. Time is also slowly getting short, as the thin layer of solid matter making up the walls of the shaft won't last forever, and sooner rather than later, the magma of Earth's inner strata will break through, not only killing our heroes, but dooming the planet as well.
Finally reaching the core, the Ducks find the Omnisolve floating around inside a small void it's eaten out of the surrounding matter, and after some dangerous manouvering, Scrooge manages to get it back into the diamond jar Gyro designed for it, but the mission is only halfway done - if the Ducks can't get back to the surface before the shaft collapses, the Omnisolve will get out again, and they will not only die a gruesome death, their entire quest will have been for nothing.
Unfortunately, the trip back up isn't nearly as smooth, as sure enough, the shaft is falling apart on both ends as a rockslide destroys the platform, and a flood of magma is shooting up from beneath them. With uncharacteristic quick thinking, Donald uses the Omnisolve-coated umbrella given to them by Gyro to create an improvised tunnel, allowing the Ducks to try to flee the magma on foot, though this gets increasingly difficult, as the air gets more and more unbreathable. They finally break into a large cavern, and much to their shock, find themselves in a surprise reunion with the Terry-Fermies, the odd, spherical creatures they first encountered during the events of Land Beneath The Ground. However, there's no time for talk, as the magma is coming right after them, and the Terry-Fermies quickly seal off the Ducks by collapsing part of the cavern ceiling. Stuck once again, Donald quickly starts on a new tunnel, and the Ducks finally get back to the surface as they find themselves stumbling into the Duckburg Tulebug River tunnel, where they run into none other than Gus Goose, on one of his rare trips into the city.
Piling into Gus's car, the Ducks race towards the Money Bin in the hopes of preventing a volcanic eruption that would wipe out Duckburg, just barely making it in time as Gyro uses the umbrella to dissolve the lava before it can breach the surface. Along with the river water flooding into the tunnel and cooling the lava, disaster is narrowly averted with only minor damages to Killmotor Hill. Not only that, but Scrooge discovers that the shaft is now filled with priceless diamonds from the Earth's inner strata, exactly what he wanted to use the Omnisolve for in the first place!
Cut to weeks later, as Gyro walks into Scrooge's office with his notes on the Universal Solvent, finding the billionaire less than pleased with his apparent success - as it turns out, he'd overlooked the small fact that the diamonds from deep inside Earth would also be much denser than the ones accessible from the surface, and it doesn't matter how rare and flawless they are, because they're so ungodly heavy, they're effectively worthless, and the whole thing has been one giant waste of money. Scrooge promises to put the notes in a safe place - namely right into the Omnisolve, so it can't ever be reproduced and cause more of a headache than it already has.
Tropes:
- Achilles' Heel: The Omnisolve cannot destroy diamond. This limiting factor was deliberately engineered by Gyro to make it possible to handle the substance at all. If nothing else, you'd need somewhere to store it without having the Omnisolve immediately eat the container.
- Apocalypse How: The nephews explain to Scrooge exactly how the Omnisolve would destroy Earth, by eating up its core, destroying its magnetic field (leaving the surface to be scoured by solar radiation) and finally causing it to be torn apart by gravitational forces.
- Biting-the-Hand Humor: Gyro demonstrates to Scrooge how effective the Omnisolve is by letting a droplet melt itself through a sequence of increasingly stronger materials. The most impervious material is a Disney contract.
- The Cameo: The Terry-Fermians, though the Ducks don't exactly have time to stop for a chat.
- Country Mouse: Gus is apparently under the impression that trying to prevent a volcanic eruption is an everyday occurence for the city, and wonders how the cityfolk stand all the hubub. Even for Duckburg, it's been a pretty eventful day.
- Did Not Think This Through: Scrooge and his inner Earth diamonds - it's not until he gets his hand on some that he discovers they're too heavy to be used for anything. He also tries to grab some of the diamonds while they're still in the shaft, even though at that point, they're still embedded in magma. Frankly, Scrooge was lucky not to lose a hand.
- Hand Wave: As the Omnisolve ate its way to the center of the Earth, the super-dense residue it left in its wake created a thin lining around the tunnel that keeps out the immense heat of the surrounding magma. However, it only gives the Ducks a temporary window of opportunity, since sooner or later the magma will melt through the layer and trap them if they don't get back to the surface fast enough.
- Hell Is That Noise: When the Omnisolve destroys something, it makes a very distinctive "GLOOORP" sound effect.
- The Needless: As he doesn't need to breathe, Little Helper is left inside the air lock to keep an eye on the shaft.
- Nice Job Breaking It, Hero: The entire problem is set in motion by Scrooge impulsively dumping the Solvent into the ground, thus necessitating a race to catch it before the Solvent reaches the planet's core.
- No Antagonist: There's no regular enemy to fight this time, the story revolves around a race against the clock to prevent disaster. The Universal Solvent itself is the cause of the disaster, but it has no mind of its own, it's just an incredibly destructive goop invented by Gyro.
- Pet the Dog: An uncharacteristically generous Scrooge tosses a coin to Little Helper as thanks for holding the door open for him. Unfortunately, the coin lands on his head, leaving Little Helper in a daze on the ground.
- Plug the Volcano: Gyro prevents Killmotor Hill from erupting this way, using the Omnisolve umbrella to dissolve the erupting lava and plugging up the shaft with diamonds. It still takes hours and only works because the Duckburg river is slowly cooling it down from the other end.
- Race Against the Clock: The Ducks have to go after the Omnisolve and retrieve it in the short window of opportunity they have before the magma in the Earth's liquid outer core reaches it. When this happens, the Omnisolve will gradually dissolve enough of the outer core until the entire planet breaks apart.
- Sealed Evil in a Can: The Omnisolve is kept inside a diamond jar where it's inert. Scrooge unknowingly causes the apocalyptic disaster by spilling all of it on the ground, requiring the Ducks to pursue the Omnisolve to contain it again.
- "Shaggy Dog" Story: All Scrooge has to show for almost getting himself and his family killed and shelling out a ton of money is a bunch of diamonds he can't even give away, and a jar full of planet-destroying goop.
- Shout-Out:
- The journey up and down the shaft takes a lot of inspiration from Journey to the Center of the Earth.
- The helmet and jetpack of The Rocketeer can be seen in Gyro's workshop, stored inside a box labeled "Abandoned Projects".
- In a Funny Background Event (well, it actually happens in the foreground, but still) Little Helper puts together a robot mouse, then dresses it up as Mickey Mouse. After pondering his creation for a moment, Little Helper decides he doesn't like it, and pushes it into the Rejects box.
- Skewed Priorities: When everything is being sucked into the shaft by the vacuum caused by the Omnisolve, Donald is more concerned with gathering up the foldable chairs left out for the press conference so Scrooge won't try and make him replace them if they're destroyed.
- Storyboarding the Apocalypse: Huey explains to Uncle Scrooge what will happen to the Earth if they don't find a way to retrieve the universal solvent that Scrooge recklessly spilled before it dissolves its way to the Earth's core, accompanied with images of giant floods and Earth's crust being cracked apart.
