Guide for Clash Royale

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Clash Royale Deck Building Guide
Synergy above all

Every time we talk about deck building in this game, synergy is the most remarkable ingredient. We all want every card to work alongside each othere, right?
Unfortunately If you are using Epic cards solely, they can’t be an excellent Deck in Clash Royale. Building a deck is not about rarity. It is about Synergy!
Defense is as important as offense

Of course you need offense to destroy the Crown Tower and win the battle but If you don’t know how to defend your Tower, you can’t win any battle. Your Deck needs a balance of offense and defense to be useful in any situation.
The Balance of Point and Splash Damage Cards

As we can see, there are 2 types of damage-inflicting cards in Clash Royale.

Point damage: Cards that deal damage to only one enemy (Musketeer, Barbarian,…). Because they can only target 1 unit at a time, they are the highest damage-inflicting units in game. They are indispensable in order to take down high HP troops (Tankers).
Splash damage: Cards that deal damage to multiple units (Witch, Baby Dragon,…). Because they have the advantage of dealing damage to multiple opposing units, they are the lowest damage-inflicting units in game. These cards are necessary for dealing with hordes of low HP units.

Melee and Range Units

We need a balance of ranged and melee troops on your Deck in Clash Royale. Ranged troops usually have high damage per second but low HP. It is very important to combine them with melee troops. We need to use the melee troops as the meat-shield for high damage ranged troops. Having too many melee troops is such a bad idea because that will make them very susceptible to splash damage. You can see how easy it is for a Valkyrie to take down all melee troops nearby, right?
Average Elixir Cost

The Average Elixir Cost is very important. You don’t want to wait 10 seconds in order to drop Card, right?
The better a Card is, the more Elixir it costs. Your Decks should have these ingredients to be a well balanced Decks in Clash Royale:
‘Average Elixir Cost’ should be between 3.5 and 4.5

After weeks, I have found it’s a good idea to have the Average that is between 3.5 and 4.5. If your AEC is higher than this, you are always struggling to constantly deploy your cards (for defending of course). If your AEC is below 3.5, although you can deploy many cards quickly but they are all low HP troops and can be wiped out by splash-damaging threats quickly.

A small note here for you: If your Average Elixir Cost is above 4, you will probably want to place the Elixir Collector into your deck (If you have it, of course).
Having at least 2 point damage-inflicting Cards

Although groups of low HP units can quickly destroy high HP cards and buildings, they can be eradicated by splash damaging Cards. Because of that, you always need to have at least 2 point damage-inflicting Cards as the backup.

Here are some examples:

Musketeer (range)
Prince (melee)
Spear Goblins (range)
Knight (melee)
Archers (range)
P.E.K.K.A or Mini P.E.K.K.A (melee)
Minions/Minion Horde (flying range)
Barbarians (melee)
Cannon
Tesla
X-bow
Inferno Tower

Having at least 3 splash damage-inflicting Cards

Splash damage-inflicting Cards are important for dealing with large hordes of troops (most players like this strategy):

Giant Skeleton
Bomb Tower
Bomber
Rocket
Baby Dragon
Princess
Ice Wizard
Arrows
Witch
Fireball
Valkyrie
Zap
Wizard
Mortar
Lightning

Gets more...