Basic Troop Attribute Guide
There are four basic attributes for the troops, namely Attack, Lethality, Defense, and Health.
Attack and Lethality determine how much damage your troops are able to deal to your enemy.

Defense is the ability of your troops to reduce the damage they receive, while Health refers to the amount of damage that can be taken.
Both Defense and Health determine how long your troops will stand as your enemy keeps dealing damage.

Basically, it is necessary to improve the 4 attributes of all your troops.
But when it comes to specific troop types, here are some tips for you.

Since the infantry troops mainly play the role of tank in the front line of combat, it’s suggested to improve the Health and Defense of your infantry troops first.
As for the Rider and Hunter troops, they are the main damage output for your troops and very vulnerable.
They are usually put in the back row when a battle starts. So, Attack and Lethality attributes should take priority when it comes to the back-row troops.