Your stack size in the game will determine how many units can be in each army. When first starting the game, you can only select few a stack slots in each army.

This number starts at four, but you can only have three units in the army. The remaining slot is reserved for a Hero or Apprentice which is marked by the star icon.

This rule goes for all mages, classes, and spell school combinations.

In this guide, we’ll cover multiple ways to increase your stack size to expand your armies significantly to thousands.

How to Increase Your Stack Size

Source: Gamers Heroes

There are a few different ways to increase your stack size.

Before you do, however, you must first upgrade your Tower. After unlocking Allfire, you can invest it into three different categories: Mana, Research, and Proficiency.

Improving your proficiency will turn into Mastery which will quickly increase your Tower’s rank. When you reach a new milestone in your Tower’s rank, you will be able to unlock new stack slots.

Improving Rooms in Your Tower

Source: Gamers Heroes

Another way to unlock new stack slots is to construct and upgrade certain buildings in your Tower.

The best way to do this is by reaching maximum friendship with the city of Audale in Gillyshire. After you have reached maximum friendship, you will then unlock the Warriors Hall blueprint.

The Warrior Hall instantly provides a further +1 to your stack slot once constructed.

You can continue this process for many other rooms in your tower. On top of increasing stack slots, you will also get additional buffs that can help in combat.

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