There are 6 scenarios in the Montezuma campaign:
1. Reign of Blood
2. The Triple Alliance
3. Quetzalcoatl
4. La Noche Triste
5. The Boiling Lake
6. Broken Spears
Win every scenario of the campaign using the cheat code “i r winner”. Then, to trigger the achievement, win any scenario of any campaign without using cheat codes. The quickest scenario is the 1st scenario of the William Wallace Learning Campaign: Marching and Fighting.