Upgrade and improve troops in Gems of War by levelling them with souls or Ascending them with extra copies of that card. Troops can also be Traited to give them extra perks and abilities.
Level troops to increase skills
Spend Souls obtained from battles to level a troop and increase its skills (attack, life, armor and magic). The maximum level you can upgrade your troop to depends on their rarity. The soul cost increases the higher the troop's base rarity is as well as the higher the level upgrade too.
|Current Rarity||Maximum Level|
The Level up menu has different presets for the maximum level (levels your troop to the maximum level of that rarity) or highest affordable level (the highest level you can afford with your total amount of Souls). If you don't want to go all the way simple use the left and right green arrows on the left to adjust the exact level you want.
NOTE: Troop upgrades including leveling, Ascending, or Traiting a troop are applied to all copies of that card - so be careful if you disenchant a troop as you will lose its traits as well!
Ascend troops for increased stats
Ascending a troop to the next rarity requires extra copies of that card and can increase the maximum level of a troop, therefore allowing you to increase the maximum stats possible that troop as well.
Why can't I ascend my troop?
If the game shows "You have x25" but the ascension screen is greyed out, this means you need an additional card to ascend the troop. For example, ascending Alchemist to Legendary requires a total of 26 cards but costs 25 so that you are left with a card to use the troop in battle. Once you have x26 Alchemists you can then make him Legendary.
TIP: Troops can also be improved by unlocking their Traits, discussed in this article: What Are Troop Traits And How Do I Get Them?.