Several feet above the surface of the western Pacific Ocean, directly above the deepest point of the Mariana Trench, a small pinprick of pitch-black forms. Slowly expanding to become the size of a small marble, it freezes for a brief moment before suddenly erupting outwards, tearing open a large rift in reality itself to form a thin yet massive vertically oriented oval of empty void. Were any creatures nearby to witness it, it would appear to them as an expanse of deep space, pitch black with twinkling specks of stars interspersed throughout.
Snaking out from the bottom of the portal's opening, a tendril of a silvery grey crystalline substance stretches out and diligently begins laying out a dense spiderweb-like pattern composed of itself, forming a platform floating a few inches above the tallest crests of the water beneath it.
Once it has finished crafting several densely filled layers, similar in methodology to that of a 3d-printer, the substance abruptly ceases its actions and retracts back into the void. Left behind is a large floating disk just beneath the lowest point of the portal, roughly the size of a small aircraft carrier.
A few seconds pass, then a long jet-black spindly leg sticks out, pressing down on the platform to test its stability. Finding it satisfactory, slowly a figure steps out of the portal.
Roughly the size of a horse, its eight-legged lower body is quite similar to that of a giant arachnid, covered in a pure black exoskeleton. Its upper body mostly resembles a human male from around the waist and up, extending from where the arachnid's head would have been located. The black segmented exoskeleton extends upward along even the human portion; covering his back, parts of the sides of his abdominal area, the topside of his arms and hands, as well as some small pointed outcroppings to cover his cheeks and forehead. His exposed flesh is a pale white, and his vertically slitted eyes are a bright green, nearly neon in color.
Bouncing up and down a few times to further experiment with the stability of the platform, he walks a small distance away from the portal. Once he stops his movements near the edge of the floating disc he takes in a slow, deep breath, filling his lungs with the area's salty air.
In short order, a parade of other mixed creatures come through the portal. Some giant and blue-skinned, some small with long trailing furry ears, and various other forms of six or eight-limbed beings. The most human-shaped of the bunch is a female with navy blue skin, standing nearly seven feet tall, with long pointed ears poking out of her hip-length midnight-blue hair.
Once he has finished slowly exhaling the deep breath he drew in, the arachnid-hybrid turns to look down at the shortest member of the party. It's barely over two feet tall, dressed in several layers of cream-colored silks with soft brown fur sticking out anywhere that its flesh would have otherwise been exposed. Its long ears would probably be dragging on the ground like a wedding train if they weren't held together with a silver clasp held up high on top of its head in a sort of elevated ponytail.
"Haaah. Professor, you weren't kidding when you said your readings detected no mana in the general atmosphere. If you didn't tell me it's all crystallized down near the planet's core, I'd think they didn't have any at all. Ugh, how could anything live like this, I feel itchy all over." Once he gently taps near the base of his left ear twice, the arachnid hybrid speaks out in flawless English, without traces of an accent of any sort.
After making his complaint, he crouches down with all eight of his long spindly legs. Once he lowers himself sufficiently, the three most diminutive members of the party climb up onto his lower back with varying degrees of elegance.
"Well, at least that means very few of them will have any use for it, we should be able to get a fairly large harvest without much protest. Here's hoping they have some technology worth integrating, I always feel like we're just running a charity when the natives don't have anything worth offering in return beyond excess mana. Everyone has their assigned coordinates, correct? Keep your personal safety a priority, they only barely meet our maximum allowed threshold of 'percentage of total world population at war', so I'm sure some of us will see some hostility. Let's go make a show of acknowledging each of their major cultures, you know the drill people." As the fuzzy Professor makes his declaration, there's a mix of confirmations from everyone present. After he makes a quick sweeping gesture a series of small hovering vehicles come out of the portal, matched in size for several of the beings in attendance.
---
Once they've scattered across the globe to grant their near-simultaneous greetings, virtually every single news platform and form of social media becomes flooded with the news of the alien arrivals as well as their message. While it is translated to each area's local primary dialect, the meaning remains the same; Humanity is being welcomed to join the 'Cross Dimensional Alliance', a communal repository of knowledge. In addition, there is an open invitation for interested humans to test their magical affinity, those that prove capable may even receive formal training in the art.
As could be expected, there is a widely varied spread of responses. Some involved guns, some involved gifts, and a few were an almost alarming amount of rule 34 art within a mere hour. The seven-foot-tall blue woman would be justified in strangling quite a few people, multiple of which would probably thank her for it.
Once the groundwork had been completely laid out and examinations for magical aptitude were conducted, only about 13% of humans tested proved to be able to draw in any quantity of mana. Within that limited populace, only a minuscule number of people had any note-worthy capacity.
Of these rare few individuals, only one dozen had opted to join with the CDA for tutelage. These few magically inclined individuals plus a delegation of scientists, which are spread across several different fields of study from every major nation, results in a group notably smaller than most worlds the CDA had previously scouted.
As a show of good faith, as well as a continual open invitation for those that opted to not yet receive any training in their potential gifts, the portal is left open with a few devices for limited control over it left behind. Needless to say, some of these devices are dissected and reverse engineered in very short order.
Built off of the original silvery crystalline platform, a crystallized magic drill is established to harvest the densely condensed mana ore from a few layers beneath the lowest point of the Mariana Trench. Once collected, nearly all of it is shipped right through the portal to the waiting CDA base.
---
After a few years spent in study, two of the initial dozen magic candidates had opted to return to earth to resume a mostly normal life. Thanks to the challenge of accessing mana they can't really use magic more than a rare few times, leaving them mostly safe to remain unsupervised. Those ten that remained have all joined the 'Unified Dimensional Preservation Force', a subdivision of the CDA responsible for managing the following; delegations for invitations, mining operations, searching for eligible worlds, the share and tutelage of magical proficiency, and a crisis task force for when knowledge is abused or there are mana-related hazards which need to be addressed.
The scientists that had been furiously working on closing the technological gap between earthlings and the rest of the unified intelligent species often need to make bets to determine a loser to have to go back to report progress as well as attempt to catch others up. The pursuit of previously unimagined knowledge is just too much of a temptation, none of them ever want to stop any longer than is absolutely necessary.
People that were once considered geniuses end up written off as idiots if they have any difficulty with catching up with the times.
While the most capable of humans had all joined forces with one wing of the UDPF or another, there are always those that have different priorities. A group of people joined together to form the 'Humanity First Federation', a coalition of individuals that had decided to utilize these new technologies and magical discoveries exclusively for the progress of, well, humanity. Able to travel not just between planets but even across parallel universes, their desire to continue independent research, as well as the acquisition of nearly limitless exotic resources, is irresistible.
---
As long as the HFF continues to keep their antics non-violent and their destruction to a minimum, they will remain largely unnoticed by the UDPF. But of course, they love to push that line every chance they get...
...Unfortunately for Celeste Yates, she constantly gets the short end of the stick, needing to go and be the one to clean up after their messes.
'Elite task force, my rear end. More like a glorified multi-dimensional nursemaid.'