In Call of War you have the choice between 34 different units (we counted Nuclear Energy as a unit) from 5 different branches: Infantry, Armor, Air, Naval and Secret. Each of these units offers a set of unique features with regard to speed on different territories and strengths or weaknesses in combat with other units (or terrain). Units have to be researched and require certain buildings. Without both you will not be able to produce them. The information button ( i ) in the research tab will tell you more about the specific units.
Each unit requires certain resources for the daily upkeep. Selecting the unit gives you a view of their Morale and current position. If the unit is marching, it will show the province the unit is relocating to, travel time and arrival time.
To raise their Morale you might either use Gold or keep them out of combat in one of your provinces. You may specify a name for certain units (battleships and nuclear bombers) - to view the name, you select it and then select the unit image.
Here you can get access to very useful info such as: enemies destroyed (HP), condition, state-based damage efficiency, battalion the unit is part of, and the unit count. Attributes of the unit can be viewed just under the unit info.
Some certain units have an attack range - you can see the range of the unit by clicking it. The white circle is as far as it can go without needing another airbase to stop at.
Armies fighting in their own core provinces receive a home defense bonus of 15%. This grants an army a 15% higher combat strength (damage output) and also reduces incoming damage by 15%.
State based damage efficiency
Damage efficiency is the overall fighting ability a stack of units have together.
More units (of the same type) makes the damage effiency go down, which means they don't fight at full power. Bigger stacks though, can absorb more damage taken. So finding a balance between the two is important during your conquests.
Attack: select a unit and give them the attack command, or just drag them to the province or unit you want to attack. If your unit garrison crosses path with a hostile army, or when its way passes the main city in a hostile province, fights will begin. If your army wins the fight, the remaining troops will execute the previously given command and commence moving into the original direction.
If you and your ally attack a province, the army that fails to get the province first, will cancel their attack.
March: moves the unit to a selected point.
Split: splits your army up.
Delay: delays the unit's movement and makes them reach their target at a certain time. Selecting multiple armies will make them reach their target at the same time.
Forced March: incrases march speed for 50% but gives a morale penalty of 5 per hour.
Add Target: grants the ability to select additional targets.