Hmm its interesting you mentioned Marienburg, cause that was the faction that I encountered spamming the pistoleers in my Chaos Campaign. I know its starts off as a small faction (maybe 3 settlements to start with) and it has a poor relationship with the Empire (they declared war on me in my Empire Campaign at turn 10). So it could be spawning armies like that again because its most of its settlements are being lost early on.

I can't say I have run into a pure mounted marauder/ chariot army yet... But then again my empire campaign didnt get very far before the game started crashing. I have run into some Chaos armies that were heavy on trolls and chariots those were pretty nasty to go against.

Marienburg only has the Wasteland, which is only 2 settlements. The city itself, and a smaller one north across the river, in a prime spot to get taken over by Middenland, Nordland, or be burned to the ground by Norscans. Yeah to get all the various Empire units you need 6 different buildings, of which 4 have to be in a major city to reach full potential.

Well I get to fight two full power and one half power Ork armies that have popped out of the Badlands. This is not fun. I just finished dealing with Goblins doing that and helping* some Dwarfs recover.

*Helping here meaning taking over their cities while they're held by Greenskins.

Finally, the Storm of Chaos that ravaged the Old World, claiming countless lives as offers for ancient and dark deities, has lifted.
Peace seems finally to have returned to the war-torn lands, where life slowly tries to return to normality, where the survivors are building new empires from the ashes of those destroyed by the warriors from the north.

However, this couldn't last for long.

The Border Princes, those who suffered the least from the Chaos that engulfed the world, have been utterly wiped out, as they were the first to be hit by the bulk of a new age of destruction, this time coming from the south.

The dwarfs hold out as much as they could, but alas, when their last Karak in the north of the World's Edge Mountains was burning and their king laid slain while still holding a book filled to the brim with unsettled grudges, their race was no more.

To the west, Tilea and Bretonnia are fighting a fierce battle for survival, but even the nobility and dignity of the grail knights can do little against such a tide of brutality and savagery.
While Brettonia tries to defend valiantly his lands, Tilea is on its last foot, and only because of the attacking warlord's temporary distraction they still resist. However, voices say that this enemy has gone to the Chaos Lands to retrieve a mysterious artifact permeated by dark energies, which his new owner has all the intentions to unleash on mankind once he returns.

Manfred's dream of creating a new Empire from the ruins of the old one where shattered the moment his last castle was put to siege. No dark sorceries, no curses cast on the land, no monstruosities were able to hold back the enemy, which slowly but steadily advanced through twisted territories careless for the attriction and the losses.

And while all this was happening, even the Norscans tribes now tremble in fear, as an other mighty lord, brutal beyond measure, has put his gaze on their country, thrilling with anticipation for the upcoming bloodshed. Even if this pleases their gods, the tribesmen can't keep up the pace with the amount of sacrifices they're offering with their own lives.

Truly, now the Old World has met those which will bring the End Times.

The Orks are coming.
Grimgor IronHide leads them.
And he isn't done fighting quite yet.

Thanks for clarifying on what Marienburg starts off with! To be honest I never gave them much thought on their diplomatic standing with the other AI, they were always a fly in the room which could be left alone in my Empire and Chaos Campaigns. It was only when they declared war on me or when I was encountering their armies in the North and in Middenland that I gave them any attention.

lol I know the feeling! Orks and Dwarves love their confederations! In the Dwarf campaign I just started up yesterday, I noticed in the research tree, there is a line which improves your diplomatic relations and economics with all factions, when you couple that with those event quest/ decision pop ups that come up from time to time which give you the ability to improve relations with a particular dwarf faction, forming confederations can be pretty quick. I am about 30ish turns in and I already have 3 military alliances and 2 defensive alliances between the dwarf factions I have encountered thus far, and my relations with these factions is only getting better with each turn.

Faction/Army Rating will also have say in how factions behave with you. Being one of the strongest factions can influence the formation of confederations between enemies as they attempt to fend you off, or it can draw other factions to want to be allies with you to ensure their own security or use your strength to take advantage of weakened enemies and expand their own holdings. I am seeing this in my Dwarf campaign and saw it in my Empire campaign.

I really wanna get the mod that disables assassins. I dont like using or fighting them.

That sounds amazing.

Apparently you have never managed to create a "black death" using a single spy have you?