Age of Empires II: Definitive Edition

This will be unlocked in the second campaign mission under Babur. Early on in the mission after claiming your first city you will receive an offer from Kabul to form a non-aggression pact. The window to accept the offer is relatively short. To unlock this achievement you need to allow the offer to lapse and then capture the monument in Kabul's city to end the mission.

Kabul is nothing special and attacks mostly with foot infantry, crossbowmen, and the occasional siege elephant.

to get the achievement you just have to ignore reds offer and continue to win the game. Thats pretty straightforward. I think the hardest part is not having reliable gold income, no access to trebuchets and the enemies having endless ressources.

Also, enemy markets are destroyed if they are defeated and red switches to your color if you conquer the monument, so you cant trade with defeated enemies.

I think the best way to deal with this is trading with red: From the starting point, there is a path west that leads you behind the red city. Behind reds base, there is a towncenter and a market. There are only a few towers on the way you have to clear.

If you put a market at the starting place and wall off the entries to the east, you can trade with red relatively safely. red just sends a single soldier once a while.

From there, just deal with the other 2 and finish red last