Age of Empires II: The Conquerors/La Noche Triste

Map
Available on the Steam website.

Walkthrough
Here you will have no villagers for quite some time, and you are playing against time because the enemy starts building a wonder. Time should just be sufficient, but remember save often and use the pause key to give you time to think.

The map is a big lake with an island in the middle and some land on the edges of the map.

Start by walking with your only unit, an upgraded strengthened Jaguar Warrior (assign a hotkey number to this unit), towards the lower right. You will find a few units and two houses. Then walk to the lower left. Avoid the enemy Jaguar Warriors in the north, kill the three Eagle Warriors, and board the ships. You will have more than 20 units, but don't lose time by sailing back and forth. Instead, delete some units (you will have to do so later anyways to stay under the population limit): the pikemen are relatively useless, you can also delete some Eagle Warriors.

Sail further towards the upper left, save your game, and land your troops. Convert one of the Conquistadors with your monk and kill the other one. Delete the two transport ships, as they are completely useless from now on and only occupy two precious population slots.

Avoid the bridge, where some enemies will wait that are too strong to fight against, rather keep to the edge of the map, until you reach a fenced area where it is suggested that you deleted part of the fence to release the beasts. You could do that, they will kill the monk and then be deleted automatically, however you can use your monk to convert the enemy monk, which then can heal your monk (who is probably more than half dead after the encounter with the Conquistador). As soon as you converted the second monk, you will have control over a Onager, immediately pause the game, or it will start attacking a few Jaguar Warriors and be destroyed. Pull up your units, especially the skirmishers and the conquistador, who make it easy to get rid of the Jaguar Warriors.

Quickly walk toward the upper right until you reach the Tlaxcaltecan village. Save your game. Don't start attacking anything. Instead, convert at least two villagers, better three, and convert a few buildings like the barracks and a few houses, not necessarily the blacksmith (avoid wasting time!). You can send your special unit towards the tower to take the arrows while your monk walks past him and converts the tower (which has no Murder Holes), the other monk can convert the mill. As soon as you have the tower, delete it instantly before it fires a single arrow, otherwise it will attack the enemy houses and thus trigger a constant stream of enemies, this trouble is really not needed at all! When you have the mill, you can put one or (if you managed to convert three) two villagers on the fields to harvest food, but at least one villager needs to be moved along with your army, and be guarded as good as the monks (i.e. if you lose it, reload a save game).

Move further, towards the prisoner area, but save your game before you reach it and the prisoners are activated. While your soldiers attack a few enemy units, crack open the wooden wall with your catapult, then keep moving toward the right as quick as possible. Your monks and the villagers need to be kept healthy in this brawl, all other units are basically expendable. Use your Conquistador to ride quickly over the bridge towards the harbor, where it discovers a bunch of ships. Steer the transport ships toward the beginning of the bridge to load the bulk of our army, and use the fire ships as escort (they won't survive long, rather use them to lure away attacking enemy ships from your transport ships). When you have loaded the villager and the monks and as many units as you could save into the transport ships (if you have more than 50 units still, sacrifice a few Eagle Warriors, keep the conquistador and the skirmishers), sail towards the upper right and then in a wide curve further right, then lower right around the whole map.

When you have reached the land on the lower right edge of the map, save your game, disembark, move the villager and the monk away from the coast, discover the monastery village and a bit to the upper right find the berry bushes. Build a towncenter here and churn out villagers. send your army units towards the bridge which is left of the village and the only way enemies might come to you. However don't build any walls, tower or similar at the bridge head, that will attract a bunch of ships. Just hold the bridge with your skirmishers. If you run into the population limit, don't stop building villagers, rather kill your soldiers, just keep the skirmishers, a bunch of jaguar warriors and two transport ships.

Now collect resources. 150 stone are enough, so you can build a castle (you might be tempted to build it near the bridge as guard, but don't put it to too close to it, as that would trigger ship attacks, including war galleons with superior range), and then use it to create 5 trebuchets (i.e. 1000 wood and 1000 gold). Don't waste ressources on any research or building other units or buildings, and reassign villagers to another resource if you have just enough of one. Remember, time is of the essence.

Don't even bother fighting your way over the bridge through several castles, coming under attack from all sides by land and sea units. Such an endeavour would certainly be possible with some effort, but takes way too long. The wonder is nearing completion, and you only have 300 years after that until you lose. So the winning strategy is a different one.

When you have the 5 trebuchets, load them into the transport ship (just one is enough but doesn't harm if you have two still), add a few good units into it (like maybe the skirmishers, the Conquistador and Jaguar Warriors) and save your game before you start your Kamikaze attack. Then try to be lucky and find your way over the ocean to the harbor where you found the transport ships without encountering enemy ships that might sink you (i.e. if you loose the ship with the trebuchets, reload). Disembark, use your soldiers to distract enemy units from your trebuchets, while they move down towards the wonder and attack it. They will be attacked by a catapult that might destroy one or two trebuchets, but your forces should last just long enough to bring down the wonder. They will inevitably perish afterwards, but just a few seconds later, Cortez will give up and you have won.