Here is the full list of all 37 Third Front achievements.
Found 500 diversionists
Complete the Alliance campaign
Complete Germany campaign
Found 125 diversionists
Earned 10,000,000
Captured all the cities
Complete the USSR campaign
250 cities are captured
500 units of equipment were purchased
200 cities are captured
The main building is improved to level 40
150 cities are captured
The main building is improved to level 30
Earned 2,500,000
100 cities are captured
The main building is improved to level 20
The population reached a mark of 100,000,000
25 diversions prevented
125 units of equipment were purchased
The population reached a mark of 50,000,000
Found 25 diversionists
50 cities are captured
25 units of equipment were purchased
10 diversions prevented
The main building is improved to level 10
The population reached a mark of 20,000,000
5 diversions prevented
Found 5 diversionists
20 cities are captured
Earned 500,000
The main building is improved to level 5
10 cities are captured
5 units of equipment were purchased
The population reached a mark of 5,000,000
Diversion prevented
3 cities are captured
Earned 50,000