Posting a David v Goliath story here
I was playing as Cumania in CK2 in 936, doing pretty well for myself. and surprisingly so as it was my first time playing as a nomad. I wanted to do a migration to the Indus Valley and essentially colonize India after settling down. Now for context I'm playing with HIP and Seljuk and the Ghaznavids spawned right to my south with 40k event troops each. Now HIP adds an option to give rulers "luck", essentially a trait that gives them extra stats and access to the same CBs as the player, this culminated with Seljuk conquering all of Persia and forming its empire title.
Now I expected that I would fight him for Transoxania and have a challenging fight, unluckily for me... The Mongols spawned in 990 with
80k troops, for context I had 8k horde troops (retinues) and could pull up to 15k with my vassals if I called them into the war. I was left with two options, either give up the whole Kingdom title of Cumania with would've wrecked my nomad population and then try to migrate south by fighting Seljuk while I was weak or fight.
The Mongols conquered a bunch of guys to my east and after some save scumming in a few failed wars I expanded my army to delay their attack on me by a year, where they eventually conquered all of East Turkestan. When the Mongols declared war on me,they could split up their armies into 17k sttacks and beat my army which at most was 12k with mercs. I called in as many bonuses as I could as the leader of my warrior lodge society which were pretty busted and even then I won against a 17k stack on a mountain tile by a hair. This left the rest of the Mongol army to deal with who were 2 tiles away from where the battle happened.
Now the funny thing about HIP is that it adds in a "siege capture" mechanic, where everyone in a given capital is either captured, killed, or let go depending on your choice. As far as I know this event fires 100% of the time. To my delight, Ghenghis Khan had gotten a severe case of food poisoning which led him to become bed-ridden and unable to lead troops, thus leaving him in the capital with his entire dynasty. I winged it as fast as I can to the Mongol capital with the entire Mongol deathstack on my trail.
With days before the siege was interrupted by the Mongol army engaging me in battle, I assaulted the Mongol capital and took it over after a single day, leaving Ghenghis Khan and his entire family in my hands. Out of spite for making save scum so many times, I wiped out his entire dynasty bar his second-born son Chagatai who was out of the capital and two of his daughters who couldn't inherit anyways. I later killed Chagatai after the war in a duel to put an end to Ghenghis Khan's bloodline.
With Ghenghis as my prisoner, I was able to win the war and got a bunch of prestige and gold from it since I was the defender, absolutely bankrupting him. Since I killed his entire family and all,he became my rival and thus I could duel him. After dueling his only living son Chagatai and putting him down, I challenged him as well to a duel
With no male left to inherit, the Mongol empire title passed onto a random guy whose horde consisted of 500 people (compared to Ghenghis' 115k, puny and tremendous by nomad standards respectively) wiping out 20k men from his 60k due to his population not being able to sustain his horde, leaving him with only 40k event spawned troops which I could more than easily deal with.
This is probably the most fun I've had in CK2 in a while, and the first real challenge I encountered outside of invading China in a while. If any of you get your hands on CK2 and all its DLC, I can't recommend playing nomads enough whether they be the Jewish Khazars, the Tengris Cumans, the Hungarians or Muslim Bolghars. This is my kill list right now.
