This Chinggis Everything

Needs Khans of the Steppe. The Greatest of Khans trait comes from winning the Great War of Defiance that fires when you take the Become the Greatest of Khans decision - Temüjin in 1178 is the natural start (and the stepping stone to The Stallion that Mounts the World). The condensed wiki playbook: yearly Nerges with Substantial Party Size as your gold/prestige/legitimacy engine (Prolific Hunters halves the cooldown - and one Excellent result is Shut Up, Nerge); expand with Nomadic Quarrels, Bring under Tribute and Expand Dominance CBs; build Heavy Horse Archers; raise Dominance, Dominate Title, then take the decision and win the war - battles cap war score at 100%, so hunt the enemy hordes while a second army takes holdings. Do NOT take Settle the Steppe, Forsake Nomadism or Convert to Local Culture along the way; they break eligibility.