Age of Mythology - Fall of the Trident: 30) All is not lost
2Scenario 30 from the Fall of the Trident Campaign.
This is a great exercise in defending.
Start off by building the settlement in the old mining town. Use your heroes to explore the area to find all the resources and relics. Go hard on the economy first for at least 5 minutes.
Once you've got enough gold, build at least two walls (I usually do 3) across all three passes. Secure that with masons, hill forts and towers and their upgrades.
For units, aim to build jarls and throwing axemen.
At some point the enemy will use underworld passage and creep in somewhere. I like this as it adds an element of surprise and it can freak the player out. Just recall your army back and wipe out the underworld passage and try not to lose too many villagers.
Once you've held out, Odysseus arrives with a strong army that you can use to push to the north of the map.