Earning this trophy is easier than it sounds.
To get to the moon stance you need to kill or observe Mongol Leaders.
These are found in:
• Mission objectives
• Within Mongol camps
• Within Mongol strongholds
• They also spawn within side missions
Observing requires you to be stealthy and not be spotted by anyone in the leaders vacinity.
It requires 20 leader kills to do the trophy, you can observe and then kill the leader to get two points towards your progress.
NOTE: Some leaders will not give you this option, so take it where possible.
They unlock in this order:
Stone (automatically unlocked)