A/N:

Set sometime in season 2 of Slugterra and season 1 of TMNT (2012). It's not that relevant, but I'm mentioning it anyway, because someone might care.

It's also probably worth it to state clearly that this is mostly about the turtles being in Slugterra, and only a little about the Shane Gang meeting the turtles.

As usual, I'm going to say this story is probably AU, though not especially intentionally so. As always, this story is completely written. As per usual, I will upload one chapter per day (Barring anything out of the ordinary. I will attempt to give readers a head's up via A/N). This was written for my entertainment, and is being published for yours. If you find yourself not enjoying it, then you should feel perfectly free to stop reading. Heap praise or criticism upon it, whichever may suit you best. Or say nothing about it at all, if you would prefer. Do feel free to point out typos, I check my stories before publishing, but I admit my imperfection and would welcome the opportunity to correct any mistakes I may have made.

It is a curious characteristic of most living things that they simply cannot (or at the very least will not) voluntarily acknowledge anything which is sudden at the most crucial moment, instead waiting for a good half second or so before deciding that suddenness happens and has indeed happened. For the especially slow witted, this half second can easily stretch into five or ten seconds, perhaps more.

The first thing to acknowledge sudden and unexpected changes is most often whatever part is responsible for fast reactions to things which are advancing quickly. This is not necessarily ideal, as this part seems wholly unattached to anything resembling logic or reason, and the reaction is not always the needed one and may even be quite a harmful one.

For Raphael, the mutant ninja turtle, the first reaction to anything was to hit it, or preferably stab it. In this case, the "it" in question, turned out to be a very large, green leaf of a perfectly innocent shrub. The leaf itself had, of course, never done anything to merit such treatment and (assuming leaves are capable of harboring such feelings) was probably quite put out about it. The shrub might even have been very offended. Its occupant certainly was.

A high pitched squeak of protest was accompanied by a slight splat as a small, squishy reddish thing dropped to the ground. Raph blinked at it without any real comprehension. It didn't look like anything he'd seen before, and so he was slow to process what it was he was looking at.

He'd seen a lot of misshapen blobs, most of them hideously ugly and incredibly vicious, but this looked neither malformed nor especially dangerous. It was an inch or two tall, reddish on the back, bluish on the front, with a distinct head and large eyes that gazed up indignantly at the monster that had just gone about demolishing its abode (or at the very least its perch).

Raph got on appallingly with people, but really rather well with most animals, especially small ones that weren't of the fuzzy, cuddly variety. He knelt down to get a closer look at the creature.

"What are you... some kind of slug?" Raph queried, putting away his sai so he could pick the thing up.

It promptly tried to bite him, then it squelched at him. Its large eyes were critical, it was evidently very offended by either Raph's approach to it or else to the leaf it had up until recently been sitting on.

"Okay, I deserved that," Raph conceded, something he never would have done with any person (or if any person had been present to bear witness), "But I'm really not such a bad guy."

The slug continued to squelch at him. It had never seen anything like him and wasn't about to take him at his word. When people claimed they weren't "such a bad guy", they very often were precisely what they said they weren't, and this particular slug knew that all too well.

Raph, for his part of the exchange, ignored it. It had suddenly dawned on him that he was very much alone, and also that this place, though clearly underground, was very much (if not entirely) unlike home.

In fact, the more he looked at it, the more certain he was that this was like no place he'd ever been. While it was a cave of sorts, and had things which were identifiably plants and rocks, nothing looked at all familiar.

Raph knew his world experience was somewhat limited, but he didn't expect that even his brother Donatello knew this place or anything in it.

Most curious of all were the slugs, who peered from every conceivable nook and cranny, all highly interested in this abrupt newcomer, yet cautious. They thought they were hidden in the shadows or under leaves, behind rocks or even hanging down from above, but Raph spotted them in droves.

Whatever these creatures might be, they were not ninja and had no idea how to hide from one.

Raph wasn't sure whether to be reassured or unsettled by the fact that the creatures, odd looking as they were to him, seemed to think he was the bizarre one in this scenario.

But what did really unsettle him was the realization that not one of his brothers -not Leonardo, not Donatello, not even Michelangelo- were here with him. He wasn't sure what the implications of that were, but he did know with grave certainty that he didn't like them (the implications) at all.

Raph remembered clearly that, moments before, he had been embroiled in battling the Kraang alongside his brothers in a Kraang building they'd found. He'd been thrown, and then a blinding flash of light... and then he'd come to be here. He felt that he could be forgiven for having stabbed the first thing that moved in front of him, seeing as the last thing that had been in front of him had been trying to kill him. But he didn't expect the slug to understand that.

The slug had continued to squelch at him all through his thought process.

"Well," Raph said aloud to himself, "I guess I better find a way out of here. Or try to find my brothers," he looked at the slug, "You don't know the way out of this cave, do you?"

To his surprise, the slug straightened perceptibly, squeaked eagerly and nodded its head, which bobbled disconcertingly atop its small body. It flapped little appendages that resembled arms, asking to be picked up. Raph held out his hand and the slug hopped onto it without hesitation.

It continued to gibber at him, now quite enthusiastic for reasons Raph wasn't sure of.

He was kind of surprised to find that the slug really wasn't slimy, which made him question his theory that it was a slug. In his experience, slugs were invariably slimy. And they very seldom talked or showed any interest in people. Come to think of it, they generally didn't have distinct limbs or heads or disconcertingly human-like mouths complete with teeth.

Still, mutants aside from himself were not unknown to Raph, so he surmised that maybe this was just a mutant slug of some kind. Still, it nagged at him that the creature didn't look at all mutated, in fact it looked as though every piece of it was meant to be that way. And there were hundreds of slugs just (or at least mostly) like it.

Some crouched or skittered away when Raph neared them, others gaped up (or down, depending on their position) at him, evidently without any kind of fear. They seemed emboldened by the fact that he was now carrying one of their number, as though this signified to them that he was not, in fact, dangerous.

Raph wondered if he ought to tell them that turtles very often ate slugs. He decided not to.

The slug in his hand gestured urgently with its limbs, pointing toward what Raph guessed must be the exit. He offered to let it ride on his shoulder, an offer it accepted with a degree of excitement that baffled him. Then, keeping one hand on a sai, Raph set off in the indicated direction.

Though the cavern seemed largely empty aside from slugs and plants, Raph kept to the shadows, uneasily aware of how few exits he had. While there was a plethora of places to hide, there were no visible escape routes, and that made him nervous. A ninja always wants at least ten viable -if non-obvious- escape routes, though in a pinch four or five will do. Raph had none, and he didn't like it.

Were his brothers also here? He wondered.

Leonardo, at the very least, had also arrived in Slugterra, though of course he didn't know the name of the place. He too quickly recognized that he was underground. However, he was not alone.

Leo had the unfortunate distinction of having been deposited directly in the main street of a town. A town whose residents were currently in hiding, though Leo didn't know that. All he knew was that he was looking at a truly alarming number of buildings, and he was nowhere near being hidden among them.

Before he could go about concealing himself in a respectable manner, the ground began to vibrate beneath his feet. Small stones in the street danced, and something that sounded upsettingly like a herd of wild animals charging toward him came from a cloud of rising dust.

Leo already had one katana drawn and now he tightened his grip on it in preparation for whatever was coming. There was no time to seek cover. Aside from which, Leo was uncertain whether such cover as he desired existed. The short huts lining the street provided little concealment, and the cave floor in his vicinity was distressingly open and lacking in shadows.

As the dust cleared, Leo was rather stunned to find himself looking at three big, metal creatures. For a moment he thought the mechanical beasts were operating independently, but he quickly realized that they were in possession of riders. This didn't really make him feel any better.

The long claws and spikes along the necks of the mechanized beasts didn't make him feel terribly secure, the sharp teeth especially set him on edge. He didn't want to find out if these things could crack his shell or not.

Easy, Leo, he admonished himself, Maybe they're friendly.

The one in the middle stepped forward, and it didn't look friendly.

"What the heck are you?" asked the thing's rider, "Some kind of giant slug?"

"I'm not a slug!" Leo snapped, bristling.

No one had ever before suggested he was a slug. He was accustomed to being accused of being a gecko (as well as assorted other types of lizard), a frog and someone wearing a costume. These insults he took very much in stride. But the suggestion that he was a slug was simply too much.

"Well whatever you are," the rider said, pulling out a rather menacing looking blaster, "You're in our way!"

Here, at last, was something Leo understood. Through absolutely no fault of his own, he was about to be fighting for his life. This was something he had come to expect when it came to meeting new people. They always seemed to think that he ought to be slightly more dead than was his preference.

But this moment of everything making sense to him was short lived.

The blaster fired, as expected. Something exited the barrel, also as expected. And it was no surprise that the thing headed right towards him. What took him totally by surprise was that it was... well... alive. With a startled yelp, Leo chose to duck rather than block the attack, and the thing flew past his head, embedded itself in the ground and subsequently exploded, knocking Leo off his feet.

Lying on his belly, rather stunned, Leo observed as a small creature went hopping past his face on a determined journey towards the rider of the mechanized beast. To Leo, it resembled nothing so much as a slug with an oddly cheeky grin on what was unquestionably its face.

Leo's scrambled brain informed him that this was clearly a product of his imagination. Slugs did not grin. They did not hop. They did not have distinct faces. And they certainly were never fired from blasters.

Leo's perception of what he was seeing and what he was certain must be refused to reconcile. They were still fighting violently as he stood up, dusted himself off- and promptly found himself diving off to the left to avoid a flaming ball of something aimed at his head.

One thing both his imagination and his logical mind agreed on, he was definitely in trouble.

With a mechanized whine, two more blasters (wielded by the two other riders) came into play, and suddenly the air was alive with zinging, flying things that all seemed to be intending to hit Leo, or at the very least explode uncomfortably close to him.

He was rapidly coming to the conclusion that, wherever he was, he didn't enjoy being here and would very much like to depart as quickly as possible, if only he could find some shadows to hide in.

But this cave (if that's what it was) was maddeningly well lit. It also seemed as if the inhabitants (if that's what was attacking him) were very much opposed to the notion of him going anywhere.

An explosion went off in front of Leo and he was thrown off his feet again. He decided that he'd had enough of this running about and being shot at. With a growl, he got to his feet.

"Alright, you want to play rough?" He hissed, gripping his katana, "Let's do this."

With that, he charged for the nearest monster robot.