Age of Empires II: Definitive Edition (PC) - Achievement - Not a Greek Tragedy
Win without losing any of your four heroes in the fifth Le Loi mission "A Three-Pronged Attack".
This achievement is fairly simple - It just takes a little care. Your forces start divided. Your have a farming village at the top left of the map, a military base near the top middle and your main town around the bottom middle with a hero in each one and two in the farming village. All you have to do is complete the mission without any of your heroes dying.
The farming village rarely, if ever gets attacked and only by a small force if it is. You can build minor defences to repel any risk of losing your two heroes there.
Your hero in the military base, you can leave there for the time being whilst you complete the secondary objective of destroying the towers and bring him to your main base when you can.
Your hero in your main base you can leave there as well. Just keep them all out of harms way. You can likely still use them to complete the mission if you like, but hiding them reduces the risk of losing them if you're after the achievement.