Antonius Varus made his way back to the pond he discovered earlier. He was quite dissatisfied with his performance. He had been supposed to gather information without being discovered.
But he had been discovered. First by a squirrel he underestimated - and that fact was ridiculous on its own - then by a little xeno horse.

Antonius knew that time was getting short. When the alien told others of its species about him, they would probably set up a search party, or even a hunting party to investigate.
That would clearly worsen his situation. He had to make first contact as soon as possible.

When Antonius arrived at the pond, he quickly cleaned his armor and equipment, making himself presentable again. He was thankful that he could get rid of the daemon filth.

While doing so, he thought about his next steps, how to achieve this first contact without causing a panic among the xenos.
Simply stomping into their village would be a bad idea. Too much initiative from his side.
Waiting until they found him was even worse. Not enough initiative.
He had to take initiative, but also had to allow the xenos to take some to prevent them from getting too scared.

Antonius chose the hilly area between the cottage and the farm as the location where he would show himself, a hilltop meant a tactical advantage, after all.
So he started walking again, keeping some distance to the route he had already used, always wary if someone was already following him.
There was no one. At least a bit of luck.

On his way, he thought about this strange planet he was on: The atmosphere, a lot of the flora and fauna - the similarities to ancient terra were obvious. And then, there were the xenos, creatures of legend from the cradle of mankind.
There had to be a secret behind all this, the probability that this was just parallel evolution was almost zero. He would try to find out what was going on here, perhaps the Imperium could make use of it in some way.

A short time later, Antonius again noticed daylight in front of him. The edge of the forest.
He stepped out onto the grass and verified his position: He could see the cottage in the distance to his right, as well as the town, and the farm with its orchard to his left. A road connected the town and the farm.

He put his bolter to the magnetic holster on his belt to look as nonthreatening as possible.
Being almost three times as big as the aliens, clad in power-armor, armed with a bolter, a chainsword and a knife that had to look like a short sword to them, that was a rather futile attempt, but still better than keeping the gun in his hands.

The Space Marine stepped onto a hilltop close to the road, not far away from the apple trees. He stood in the bright daylight, his armor glistening in the sun that stood high in the sky. He had selected the location of the first contact, now he would wait for the horses to take action.
He did not have to wait long.

Just a few minutes later, he spotted two of them on the road from the farm as they came out of the orchard.
One was about the size of the pegasus he had already seen, had orange fur, yellow mane and tail and a... stetson on its head.
This planet kept getting weirder and weirder.
At least it resembled a rather normal horse, so no wings, but a branding of three red apples.
The second one was smaller, and, to be honest, cute enough that even battle-hardened veterans of the Imperial Guard would immediately start to 'Squee!'. Its fur was yellow, it had a red mane and tail and a big pink bow in its mane. Intriguingly, it had no branding.

This little one noticed Antonius first. It stopped abruptly and stared at him, shouting

"Applejack, look! What's that thingy over there?"

Thingy?
Well, he would forgive her this insult.

"I don't know, Applebloom, but it looks kinda dangerous."

The orange one - with the hat - had stopped and looked at the Space Marine. She had a strange pronunciation, but was still intelligible. Thanks to his Lyman's Ear and the acoustic sensors in his helmet, Antonius was able to hear every word they spoke, and that included the names of these aliens.
Apple farmers with apple-based names. Was the name picked according to their profession or the other way round?
Well, that question would have to wait until later.

"I don't know. It looks... quite chubby..." said Applebloom.

Chubby? Another - unintentional - insult.
Why did this creature think he was chubby? Perhaps the pauldrons...

"You don't dare go near this... whatever. Follow me and stay quiet."

This 'Applejack' was obviously cautious. Good. That would prevent her from doing something stupid - hopefully.

They slowly walked towards the town. Applejack was always keeping herself between the little horse and the marine. When they reached the point on the road closest to the him, she whispered to Applebloom:

"Go and tell Twilight to come here at once. I'll stay here and watch it."

Applebloom dashed off towards the town, Applejack turned towards Antonius. He could see big eyes with green irises watching him. The mare came a bit closer and set down. Obviously, she wanted to wait for this 'Twilight', whoever he, she, or it was.

The Astartes wondered if he should do anything, but decided against it.
He would let them pick their pace. Rushing this wouldn't be good.

A few minutes later, Applebloom returned, and she was not alone. She was accompanied by a purple... unicorn.
In the name of the Emperor, how many legends had become true on this world?
Antonius guessed that the newcomer had to be 'Twilight'.

"Hello Applejack. Applebloom told me you have a strange cre... WHAT IN CELESTIA'S NAME?"

She had spotted him and ran to the place where the orange pony was still sitting.

"Nothing you see all day, right, sugarcube?" whispered Applejack.

"Right," Twilight whispered back.

"Any idea was it is?"

"Not really. I've never seen anything like it before. Looks a bit like a minotaur."

Minotaurs? Another legend covered. What was next? Dragons?

"A bit strange, even for a minotaur," Applejack opined.

"I think it's the creature Fluttershy scared off this morning".

Scared off? He was definitely NOT scared off. It was a tactical retreat.

"I don't think it can be scared off that easily - if it's even possible to scare it off at all."

Better. Applejack was obviously an intelligent alien.

"Well, it retreated into the Everfree. But we can't stay here talking about it. We must talk TO it. But we must be careful. One giant creature rampaging through Ponyville a week is really enough. I should have brought my book about first contacts..."

"You have a book about first contacts?"

"Sort of... Diplomacy 101."

"Forget that I asked." Applejack turned to Applebloom:
"You'll stay here, we'll go."

"Hey, I wanna go, too!"

"No discussion, little sister. You stay here!"

Applebloom pouted, but did as she was told. The other two came closer.

A very interesting conversation. Antonius had learned a bit about the world these creatures lived in. The part about the 'giant creature' was especially interesting. And he knew that the next conversation would be even more interesting.

Twilight had never seen a creature like this one.
A huge biped in some kind of blue armor. On the centre of its chest piece was a winged, golden skull, but without the muzzle ponies had.
It fitted the design of its helmet, which looked like frowning and showed malevolent red eyes.
The rims of the massive pauldrons were golden like the skull and its wings. On those pauldrons was some kind of insignia, but Twilight could not really see it, the creature was too broad.
The creature's arms ended in some kind of armored claws or paws.

On its right hip hung a black box of some sort, almost as long as she was tall. She had no idea what this thing could be.
What the giant creature wore on its left hip was much more frightening: an enormous sword with a serrated edge, looking incredibly brutal. The whole creature looked like some kind of exaggerated warrior-character out of Spike's comic books - not that she read them.
But she wouldn't judge the creature by the looks. It did not even try to harm her friend Fluttershy, after all.

As she got closer, an old memory came to the surface of her mind: Hadn't she once read a fairytale about creatures that basically looked like that? What were they called? 'Humins'? Those creatures Lyra was so crazy about...
Fiddlesticks.
She hadn't paid too much attention to this non-scientific nonsense. Perhaps she could ask Lyra later, but now, there were more important things to do. They were at a good distance to the giant, not too close, not too far away.
So, Twilight stopped. Applejack did the same.
Time for Twilight to talk.

"Hello stranger, and welcome to Ponyville!" She waved a hoof in the direction of her hometown.
"My name is Twilight Sparkle and this is my friend Applejack. May I ask who you are, where you are from, what you want here and how we can help you?"
She gave the giant a warm smile.

Then, it - no, he - spoke, a deep, metallic rattling:

"Greetings, inhabitants of this world. I am Brother Antonius Varus, Ultramarines second company, Imperium of Mankind. I came to your planet because of a teleporter accident. I mean you no harm."

The ponies stared at Antonius, their jaws wide open.

"World? Planet? You mean, you are an alien? And you can understand me? And what are 'Ultramarines'? Oh, I have a million questions!"

Twilight was very enthusiastic. She had just made contact to an alien! A real alien, full of knowledge of other worlds.
Her smile grew bigger.
The giant just looked at her.

"So it would seem. Let me answer your first two questions:
From your point of view, I am an alien. I would prefer if you used my name to address me, though.
I can understand you, because the language you use is well known in the Imperium. It's called 'Low Gothic'. Who taught you this language?"

Twilight's mind was extremely busy now. The Equestrian she spoke was this alien's 'Low Gothic'? That was impossible, wasn't it?

"Well, we speak this language we call 'Equestrian' for several thousand years now. I don't think we really were taught this language, but perhaps we can find a book about its origin in my library. Well, it's not really my library, but I live there.
May I invite you to pay me a visit? We can discuss every question each of us has there."

Applejack was shocked as she heard her friend say this.
They had no idea what this creature really was, and Twilight was so eager that she had invited it to her home?
What if it was dangerous? It certainly looked dangerous.
What was she supposed to do?
Tell Twilight that this was a bad idea? In front of the giant?
Drag Twilight away to tell her?
She couldn't do anything.
No. That was not right. There was one thing she could do.

"Hey, Twilight, I think it may be a good idea to fetch the girls so we all can help you answer the questions our guest might have."

Twilight looked at her for a moment, then she understood the hidden meaning in Applejack's remark.

"Hmm... good idea. You fetch our friends, I take Mr. Varus on a trip through the town. We'll meet in the library."

She turned towards Antonius:

"Would that be okay with you?"

He nodded.

"Acceptable. Lead the way."

Author's Notes:

I've added the "Comedy"-tag to show that the story is not meant to be taken dead-serious.