- Objective: Build and protect the wonder.
Strategy 1
Building the wonder triggers increased enemy response, so preparing a bit before starting building it could be smart. Don't bother attacking enemy bases, as it just gives the other enemies the time they need to destroy your base. Try not to lose towers and castles. When sending cavalry units to kill enemy siege weapons, don't get caught up in a fight with any other enemy forces; you want to lead them in to the range of the castles. Building the wonder takes a long time, so set all your workers to construct it. The timer itself is relatively fast.
Strategy 2
There is a very easy (yet not as glorious) way to win this scenario. Northwest to your city lies an island which is large enough for you to build your wonder on. This will require you to abandon your city to the enemy, but the good part is that you will not have to bother fighting them at all.
At the beginning, research "bracer" at the blacksmith, then task your fishing ships to fishing, your villagers by the town center to lumbering and your villagers by the mines to stone mining. Use all the extra food that you will get to create more villagers and task them to stone mining.
While the enemy starts rushing to your walls and towers, create three transport ships (two should be enough if you decide to leave your army behind). As soon as the enemy becomes a threat to your villagers (when your watchmen tell you "Templars preparing to attack" should be a good time for you to leave), board them on the ships and head for the island.
When you reach the island, have a few villagers build ten to twenty towers around the island to protect you from genoese warships, the only enemy units which can still attack you (but they are not a big threat). The southern part of the island is where you will want to build your wonder, so make sure to leave enough room. Task the other villagers on the wood and gold.
Once you have collected all the gold from the southern mines, you can start building your wonder. If you don't have enough stone left, build a market to get what you need then destroy it. From now on, you just have to wait for your wonder to be completed and for the timer to run out.
Strategy 3
Take all your starting military units, (apart from the mangonels) and 5 villagers to the left hand side of the map and go up until you find a gold patch. Immediately build a castle and a town centre, use the military units to fend off any paladins. At home start mining gold and build a tc next to the gold and iron mines, get a villager to build a mill and start producing villagers on farms and gold. Fishing ships should get going as well. Once the castle is built get two trebs and then with those 5 villagers build a town centre in between the gold and the trees and start chopping the wood. With the trebs start attacking the teutons and the franks, going for the towers, then the town centre, then the teutons castle. You will get hit by some French bombard cannons, siege rams and hand can'rs first, use your units to take them out. Getting a monastery then a monk wouldn't go amiss either. The trebs should be doing a lot of damage, you will get attacked by some paladins and some teutonic knights, but the marmelukes, archers of the eyes and cav archers should be more than enough to see them off. Once you've taken out the castle, go for the villagers while the trebs take out the rest of the buildings. The Franks and the Teutons will soon resign. While all this is happeneing don't forget to make sure that your producing villagers to bring in the resources. Your main base is never attacked, but if so, the mangonels and towers will defend you. I have 11 lumberjacks, 15 farmers and 15 miners. I delete the 4 galleons and fiishing ships once the franks and teutons go down. With your trebs and cav archers, venice is easy, trebs take town towers then town centre then docks, and cav archers take out villagers.
However when attacking venice, you will get hit by the British and Jerusalem. They will attack the castle and the tc that you have built at the start of the mission. Start producing marmelukes once the teutons and franks are down. Don't forget to start mining stone, and get an extra castle or two there to help defend. Use marmelukes to take out the trebs that Jerusalem and the British send you and then send tham back into your castle. Ignore the longbowmen and let the castle take out the scoprions, mangonels, camels and champions that they send at you.
You then get the elite war elelphants from the Persians around this point. When they arrive, get an army of 6 trebs, 5 we, 15/20 marmelukes and 10/15 cav archers(delete wome villagers to make room for them). Send the War Elephnats into the British base as a decoy to take all the abuse(use them on the defensive trebs as a priority thou), the trebs can hit the castle and the cavalry to take out the onagers and archers. Once one castle is down, concentrate on the other castle. You may well lose all your units as longbowmen are annoying with that range and Jerusalem usually sends in its onagers, camels and champs as well, so don't forget to have the 3 casltes you have built continually sending in re-inforcements, and a villager building a castle right next to the British base when you attack them first is a good idea so trebs can spawn right next to them. The French may get some villagers to escape and rebuild, but they will no longer be a threat. You can now build a wonder, or rebuild your army and take out Jerusalem. As you now control most of the map with tons of resources its a very fun and easy mission.