The Horse Lords Add-on for Crusader Kings II has 11 achievements.
As a steppe horde, conquer the whole steppe region.
Start in Western Europe and completely conquer the region of Mongolia.
As a Norse character, become King of Mongolia.
Build 3 fully upgraded silk road trade posts.
Settle a steppe mercenary with more than 20 martial in your lands.
Defeat a sibling in a war using the rival casus belli.
Conquer Constantinople as a Turkic steppe horde.
As a steppe horde, have an independent tributary King or Emperor in the British Isles
Own all the silk route ports in india as a European merchant republic.
Play as a character with Wolf's Blood.
As a steppe horde, have a population of 150 000.