Disclaimer: I own neither Digimon nor RWBY

At first they were all still, confused and uncertain, Ruby holding the weakened Huckmon in her arms as they tried to figure out what the explosion was all about.

"What was that?" Yang asked. "What was that explo-"

She never got to finish her sentence as a loud howl filled the air.

"Oh no, Grimm." Oobleck said, fear etched onto his features as he clutched his arm.

"Where does that tunnel lead?" Blake asked, a creeping worry slowly spreading its chill through her.

"It should lead back to- No… It couldn't be…" The teacher's face distorted into despair as he realised what exactly was happening.

"They're trying to lead the Grimm into Vale…" The raven-haired Faunus trembled as her worry became realisation.

The other girls gasped as they realised how likely this was to be true.

"This is no good. We need to find a way out of Mountain Glenn, before we are overrun." Oobleck said as the many sounds of Grimm reached them.

Growling, hissing, screeching, slithering and heavy steps to name but a few of the sounds they could hear.

Even if most of the beasts were headed for Vale, presumably drawn by the chain of explosions and the negative emotions of the suicidal White Fang, it was only a matter of time before they were discovered.

A loud growl drew their gazes up, towards the roof… and the hole left by Beelzebumon's exit. There, looking down at them, was a Beowulf Alpha, no doubt considering how to get down there.

"Uh… I'm afraid to ask this Doctor but… can you still fight?" Yang queried, although her grim expression revealed her doubt.

"Unfortunately, my Aura is depleted, and I believe my arm might be broken." The Doctor said, carefully trying to move his arm, and promptly wincing. "I am in no state to fight any Grimm of a substantial threat level."

"Thought so." The brawler said as she readied herself.

"Huckmon, what about you? Can you move?" Ruby asked the being in her arms.

"No… I'm sorry… I… need time to recover…" Huckmon responded.

"Follow the train? Too many Grimm, judging by the sound." Oobleck mused. "Back the way we came? Straight into Mountain Glenn, extraction unlikely at this juncture… Girls! Go towards the tunnel Torchwick went into!"

They took a few moments to consider, but eventually they dashed off, heading towards the place that Beelzebumon emerged from, Ruby carrying Huckmon.

If Roman went there, there was probably an escape route available there.

It was their best bet.

Seeing its prey start running, the Beowulf Alpha decided to leap straight into the hole, and while it certainly didn't sound like it ended overly well, it still rose up, unleashing a fierce howl.

From the direction of the train tracks came several replies, many of a kind the girls were in no hurry to fight right now.

Blake quickly finished the Alpha off, using all speed she could muster to reach it, and kill it, in as short a time as possible. While it was injured, it was most certainly smarter not to leave it alone. One could never tell with Alphas what they might do, and an injury like that would only stop it for a limited amount of time.

Unfortunately, a group of Beowulves appeared along the tracks, and it didn't seem like they could get to the tunnel before they reached them.

Yang and Weiss dashed forward, unleashing their respective attacks to thin the pack before engaging.

This bought the others enough time to reach the entrance.

"Weiss! Yang! Hurry!" Ruby shouted, indicating that the two should start heading towards the entrance.

But as they started to withdraw, the ground trembled, a horrible sound reverberating down the massive tunnel the train had gone into…

And a King Taijitu emerged, closely followed by a number of Deathstalkers… and a horde of smaller Grimm.

Simultaneously the remaining Beowulves threw themselves at the two, delaying them just long enough for the massive serpentine Grimm to reach them.

It lunged, massive fangs poised to tear the girls apart.

A large blur of gold and white smashed into the beast with a great roar, tearing it apart with the mere collision.

Huckmon immediately perked up, noting the newcomer's presence.

"This power is… What are you doing here Dynasmon?" It said.

Indeed, the blur turned out to be the large, armoured, draconian form of Dynasmon, who seemed to be regarding the dissolving King Taijitu with surprise.

He was about the same size as Beelzebumon, but bulkier, both due to the armour and the muscles that showed. Its large wings only served to make it more imposing as it casually tore a few of the Deathstalkers apart.

Then it seemed to glitch out, various parts of it pixelating, and the Royal Knight went down to one knee, clear distress in its eyes.

"That idiot…" Huckmon said, then seemed to gather itself. "Dynasmon! Regress! You can't maintain your Ultimate form!"

Dynasmon's eyes widened as his head whipped around to look at Huckmon. Then it facepalmed and became enveloped in a bright light that then fell away to reveal a small, shorter than Weiss and slightly humanoid being with blue skin, large red eyes, a golden V-shape between said eyes, a sharp nose with an absolutely tiny horn. It had three claws on its feet and a tail, but it might still be possible to convince someone it was actually a small child in a costume.

Unfortunately, it failed to solve the problem, the Digimon was still unable to move, and if anything seemed to be closer to breaking apart.

"Damn, it used up too much energy before regressing…" Huckmon murmured.

Even if it was uncertain what was going on, a Creep decided to seize the moment and strike at the newcomer, but it was given an explosive right to the face by Yang.

"I don't quite get what's going on, but you saved us and took care of the big Grimm, so it's only fair that I save you and take care of the small ones." She said, offering a hand to the Digimon.

"Heh, that's honourable of you, if I had the opportunity I would have loved to fight alongside you." It replied, mustering a little bit of strength to clasp her hand.

"Aw, don't say it like that, makes me feel like fighting alongside you as well." She replied with a grin.

Suddenly a small light radiated from the two, barely noticeable unless you were looking right at them, one golden yellow and one silvery light-blue, and the Digimon's very existence suddenly stabilised as new power surged into it.

Startled they let go of each other's hands, only to realise that Yang suddenly held a device in her hand much like the one Ruby has, but this one was yellow with some small hints of red.

"What just happened?" Yang asked, staring at the device.

"Is that a…? Heh." The Digimon smiled ferociously. "It seems we'll get to fight together after all! For now, you can call me V-mon!"

"Eh? O-okay…" At first the brawler was confused, but then a similar smile came to her features. "I don't quite get what is happening, but let's rock! You can call me Yang, V-mon!"

"I'm glad that you're both fired up all of a sudden, but it would be nice if you actually got to the part where you actually fight!" Weiss interjected, stabbing another Creep. "Or better yet, returned to the plan!"

"Oh right, need to get out of here. We'll break through and head towards the others!" Yang responded, and the new formed combination burst into action, both of them delivering punishing punches to any Grimm that got in their way.

With their new fighting spirit and reinforcement, they pushed through to the entrance where the others were waiting, and they all fled into it.

-Break—

It was chaos.

Grimm rampaged through the streets, and in multiple locations Huntsmen and Huntresses struggled to contain them.

The Atlesian forces that had recently arrived had added their power though, and the source of the incursion was rapidly being cleared and handled.

It supposed it would have to give the humans some credit for the rapid response and containment of the situation.

Almost absentmindedly Lavender smashed the Pile Bunker covering its right forearm into a large Ursa, the activation of the weapon pulverising the beast.

Too weak. That the humans had trouble with these beasts was their greatest fault.

Although…

To be fair, the beasts were numerous enough that even it found dealing with them troublesome, especially since it couldn't use its Spiral Masquerade, which was its go to when dealing with weaker foes.

Of course, normally it wouldn't be facing the rabble at all, rather letting its loyal Knightmon deal with the nuisances.

Still, for all that it would like to complain, it did understand that in order to maintain their cover they needed to assist in this matter. Even if in reality it would like nothing better than to cast off this silly disguise, it did have to admit that it didn't know what to do.

So it would follow Alphamon's plan. After all, the Aloof Hermit might have been eccentric, but at least that one had an understanding of what they were doing. It had tried to figure out a plan of its own, but it had to admit that none had come to it that didn't involve being far too conspicuous.

And the instruction to remain inconspicuous had come from Yggdrasil itself. And as an esteemed Royal Knight it was unthinkable to defy the orders of its liege.

It watched as Omegos used the Grey Sword to cleave through several of the beasts at once.

While normally the weapon would be attached to its arm, right now the weapon took the form of an actual sword. While the blade remained the same, albeit far smaller than normal, it now possessed a guard shaped vaguely like the head of WarGreymon and a hilt that would comfortably allow for both one- and two-handed wielding.

At the moment his comrade was wielding it in two hands, while the modified Garuru Cannon hung on its back. The cannon remained mostly the same as when it was one of Omegamon's hands, but it had two grips, being unwieldy for a human, meaning that Omegos preferred not to use it with one hand, even if it could, as well as a slot for adding ammunition, as in its current state it would be unwise to power the weapon with its own energy.

Neither of them had clad themselves in armour, as they deemed it unnecessary to waste the extra energy needed to maintain it. Albion's example of wasteful use was still fresh in their minds, and they had no intention of repeating mistakes they had seen examples of.

In the distance Riina casually sidestepped a swipe from an Ursa, then equally casually lopped its head off with a smooth swing of its sword.

LordKnightmon could count the number of times it had seen that sword on its hand. It was rare enough to see Alphamon fight, rarer still were the times where it would actually use its own blade instead of the 王竜剣(OuRyuuKen) or simply blast them with its energy beams.

Seeing that there were no more Grimm in the immediate vicinity, Lavender relaxed, and started considering whatever or not to tell that silly woman that had been observing them the whole time to cease, or if it would be more prudent to simply pretend it didn't know about it.

But before the Royal Knight in disguise could come to a decision, the woman left, presumably having realised that she wouldn't see any more of their combat ability.

Not that she had seen anything of use beyond their various primary weapons, and even that was misleading. She still didn't know about the devastating waves of energy the Grey Sword could unleash, she hadn't seen the power of Urgent Fear. Even in these forms they could still unleash these attacks, although unfortunately they probably wouldn't be able to use them repeatedly.

If they could increase the amount of energy available to them on the other hand…

Then maybe they could even fight on the level of a Perfect for a short while…

Author's notes: It's been a tad bit longer than I had originally intended, but let's just say things happened and I didn't get anything done. I was actually a bit uncertain how to do these events, but I think what I came up with works pretty decently. I actually think that Yang and Dynasmon has a few things in common, which is why I chose him. Now to figure out if any of the other Royal Knights have anything in common with Weiss or Blake... And please don't say Blake and Duftmon because cat. I mean personality wise.

Also, yes, I know there are already two Royal Knights that have V-mon as their Child-level, but I couldn't find any other evolution line that felt like it would reasonably be able to end up with Dynasmon. Seriously though, what is up with the number of Royal Knights with V-mon in their line? Also, is there any media where Alphamon actually uses GradAlpha? I suppose maybe the one that introduced Alphamon and that actually has OuRyuumon in it?

If you see any mistakes or think I could have done something better differently, feel free to say so, it would be most appreciated.

I hope you enjoyed, and that you have a nice day.