Hi, I have made a custom mission for allied nations. It may be related to the main storyline, or not at all.
I also tested the difficulty on mental and normal. The result is the enemies can be so hard to handle if you don't prepare your base defenses and guards earlier before 2 massive enemy attack waves. And due to many troops targeting at various targets at the same moment, the game can become slower, so destroying the enemy bases is the major solution for the issue.
Download this mission here. The mission is named Uninvited Guest.
Enjoy the mission. Find me some bugs in the missions so I can do an improvement for the mission. Thanks.