This is mission 3 in the Stronghold Crusader skirmish trail.
Allies: 1 Richard
Enemies: 2 Caliphs (yellow, blue)
Game mode: deathmatch, 10000 gold (human-computer each)
This map is relatively easy. Build a granary, market, engineers guild and mercenary post. Use your starting gold to build as many catapults and fire ballistae as you can, as well as 20 assassins and a few more archers to defend your keep. Sell your goods in the market to get as much gold as possible. Build 3 apple farms on the nearby oasis, but don't worry about anything else regarding the economy of your castle. Then attack the Caliph to the top left, keeping your catapults back, firing them at the walls well out of range of the archers on the towers. Keep the fire ballistae nearby on aggressive mode to defend the catapults against any attacks. Once all the towers are out, start destroying his buildings. Move the fire ballistae forward within range of his keep, using the fire ballistae to fire at the archers, fire throwers and swordsmen on his keep. Then once these are dead, move the assassins in to kill the lord.
While this is happening, the second Caliph should be busy with the Lionheart and should not attack you. Once you have killed the first Caliph, ask Richard to attack the remaining Caliph. This will distract the Caliph, meaning he is less likely to sally forth and attack you when you besiege him. Then move your remaining catapults just within firing range of his walls on the north side of his castle (but not within firing range of his tower mounted archers). Also move your fire ballistae here simultaneously to protect the catapults. Use the catapults to take out his towers, move the fire ballistae forward and clear his keep of men then train some more assassins to take out the lord.