The Mountain Siege is the second scenario in the Le Loi Campaign in Age of Empires II HD: Rise of the Rajas. It is about how Le Loi and his forces defending the fortress from the Chinese invasion, while trying to escape at the same time.
- Le Lai (Vietnamese) are located in the center. Their forces consists of Rattan Archers, Battle Elephants, Onagers and Halberdiers.
- Vietnamese Army (Vietnamese) are located in the center. Their base is small, but quite well-fortified. Their forces consists of Rattan Archers and Halberdiers. After the first wave of attack by the enemy is repulsed, they will give all their units and buildings to the player.
- Ming Army (Chinese) are scattered around the player's base. They have a huge amount of forces, consisting of Chu Ko Nus, Arbalests, Halberdiers, Champions, Onagers, Scorpions and Trebuchets.
- Ming Army (Chinese) are located to the northwest, southwest, southeast, and northeast. They have a large amount of forces consisting of Chu Ko Nus, Arbalests, Halberdiers, Champions, Onagers and Scorpions.
- Le Loi must survive
- At least one Castle in the fortress must keep standing
- Destroy the two towers guarding the road east
- Twenty allied soldiers must escape east
- Le Loi must escape east
- Le Loi is restricted to 150 population because of the lack of supplies
- Make sure to defend the gates at all cost. Once they are breached it will be much harder to defend the fortress
- Most resources can be found out east so try to clear it for your villagers
- Due to a shortage in supplies, the construction of siege units is impossible
In the beginning, after receiving the fortress from the Vietnamese Army while the Ming start to attack, garrison Le Loi into the Castle and at the meantime, produce Villagers to gather resources as many resources as possible in the base, or send them to the east to gather more (don't forget to send some military units to protect them), and build some buildings such as Stable or some Towers to defend the base.
Train some soldiers (particularly Battle Elephants, if possible upgrade them to Elite Battle Elephants) and Monks and join with the army that was given in the beginning and divide them into two forces: one that will defend the fortress and the others that will go to the east. This way, the player may be attacked by the Ming but they will just have some small groups. Minimize casualties, and head to the east and destroy the two towers guarding the road to the east.
Once all the towers are destroyed, some Vietnamese soldiers (usually a group consisting of Halberdiers and Rattan Archers) will start leaving the fortress, and the player must cover the retreat (by sending some of the player's army to protect them until they reach the road east). Meanwhile, the Ming will continue their attack.
After 20 soldiers reach the destination, send Le Loi to the east road to win the scenario, and make sure he still alive by send some soldiers protect him.
- This scenario is based on the story Le Lai rescued Lord, in which Le Lai disguised himself as Le Loi by wearing his cape and led 500 troops, with 2 elephants, to attack the Ming and give Le Loi and his army enough time to escape. Le Lai's plan was successful but he was captured and executed by the Ming while his troops were crushed in the battle.
- Le Lai appears in the Monastery in the fortress to attack the Ming after Le Loi reach the east.
- However, this is ahistorical, as Le Lai led his army to lure the Ming out of the mountain to give Le Loi and the others enough time to escaped at the meantime whereas in the game, Le Lai appeared solitary after Le Loi and the Vietnamese army escaped.