You can invade other players to expand your own empire using the Attack Room. To increase your chances of success and allow sufficient defense to remain available in your own empire, it is recommended to use your probes to gather intel on their available military before attacking.

Home Leader War Leader #1 War Leader #2 War Leader #3 War Leader #4
Soldiers 5,500 0 0 0 0
Troopers 0 0 0 0 0
Tanks 50,000 10,000 500 0 0

War Leaders
Depenending on the sector's state, there are upto 4 War Leaders available to send out. You can send them individually, or you can group multiple leaders into 1 attack. Each additional leader sent will increase the offensive strength by 3% after the first leader, and some of your troops will return faster than the others.

Activate War Shields
You can use extra power to protect your military being sent out to attack. This will reduce your offensive losses by upto 50%. Mechanical units (Tanks, Tactical Fithers and Fighters) require 15 power each, all other units require 5 power each. In the event you do not have sufficient power to fully shield your units, partial shielding will be provided and you will be left with 1 power remaining.

War Honor
Your empire gains honor through making honorable attacks on other empires. A defending kingdom only looses 90% of the honor gained by the victor. During war time, a successful attack will gain 4 times the honor gains while the looser only suffers 1/2 the honor loss.

Target's Networth Honor Gained
< 25% None
26-49% 1.25%
50-69% 2.50%
70-89% 5.00%
90-99% 7.50%
100% and up 10%

Empire's Honor Bonus
0-599 -5.0% Income
600-1199 -2.5% Income
1200-1500 None
1501-1800 +2.5% Income
1801-2100 +5.0% Income
2101-2400 +5.0% Income, -5.0% Training Costs
2401-2700 +6.0% Income, -5.0% Training Costs
2701-3000 +7.0% Income, -5.0% Training Costs
3001-3300 +8.0% Income, -5.0% Training Costs
3301-3600 +9.0% Income, -5.0% Training Costs
3601-5000 +10.0% Income, -5.0% Training Costs
5001+ +10.0% Income, -10.0% Training Costs

Defenseless Targets
If you happen to get lucky and come accross a target who's sent too many units out leaving themselves open, you may be tempted to take advantage of this. Don't under-estimate the power of it's people however. Even without military defense, the people will still put up a fight against you. For every land the target has, the target gains 2 defensive points. This only takes effect if the total defense points of military is lower then total defense points of land.

MA Protection
MA Protection is a method of trying to lower the losses of someone who has been attacked multiple times. If you get attacked, your MA protection level will rise. The higher your MA level rises, the less land someone can take per attack.