In most arena battlers, your account level (often represented as a King Tower or Base Headquarters) dictates the health and damage of your main defensive structures.
Many players inadvertently stall their base progression by hoarding resources or ignoring the social systems of the game.
The Primary Source: Upgrading Cards
The vast majority of your account experience will come from the simple act of upgrading your cards.
If your sole goal is to level up your king tower quickly, upgrading all of your low-level cards evenly is the most cost-effective method.
Your deck is your sword.If you have excess gold, upgrade your level 1 cards to level 6.Balance is required.
XP Through Generosity
This is a massive progression error; donating provides both gold and crucial experience points instantly.
This is why joining an active clan of fifty people who constantly request cards is absolutely mandatory for free-to-play users.
Guild RequestExperience GainedCommon CardsConsistent, reliable progressionRare and Epic CardsOnly donate if you do not use the card
The Margin of Victory
If your king tower was one level higher, it would possess several hundred more hitpoints, turning that loss into a win.
A higher level tower might kill a goblin in two shots instead of three, preventing thousands of points of chip damage over a match.
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