Breakthrough mechanic

[xstatic]

Can someone explain me how it exactly works?

[GenericArchangel]

Breakthrough allows you to ignore a division's defense and entrenchment bonuses, to an extent. Without getting into the nitty gritty of this game's stat system, a higher breakthrough basically lets more of your attacks do damage to the enemy because defense lets them ignore attacks. This is why tanks are so great: they can have such a high breakthrough that infantry sometimes has to take all of their attacks, getting decimated in the process.

[spike2071]

Unless something has changed recently, Breakthrough is just the attacking divisions' version of the Defense stat.

If you're attacking, you avoid enemy attacks against you based on your Breakthrough stat. If you're defending, you avoid enemy attacks against you based on your Defense stat.

[bubbas]

Originally posted by im☭ninja():

Can someone explain me how it exactly works?

Do you mean the stat breakthrough or what?
If so then this is the definition of it:

Breakthrough. Represents the number of defenses the division has when attacking, that is, how many of the defender's attacks it can avoid. When it has no defenses left, it is more probable that the division will be hit when in combat and cannot sustain the offensive as well.

Pretty much everything Gabriel said is wrong.