Understanding Card Rarity and Type

One of the most fundamental aspects of building a strong deck in Clash Royale is understanding the rarity and types of cards you are working with. There are five different card rarities in Clash Royale: Common, Rare, Epic, Legendary, and Champion (Evolutions excluded). And there are four types of cards which are: Troops, Spells, Buildings, and the newly introduced concept of Tower Troops.

Card Rarities

Common Cards

Common cards are the most frequently found type of cards in Clash Royale. As the name suggests, they are the easiest cards to come by thus making them having the largest card count during upgrades. Common cards are usually used to fill the basic roles in a deck, such as providing basic damage, area damage, or tanking. They are generally quite versatile and can be used in a variety of different decks. Alongside their basic roles in the Clash Universe, this rarity can be associated with the color gray.

Rare Cards

Rare cards are the next step up from common cards, and they are generally slightly more difficult to come by. Rare cards are usually used to fill specific roles in a deck, and as a result, they are often harder to substitute. Alongside their more individualistic characterization in the Clash Universe, this rarity can be associated with the color orange.

Epic Cards

Epic cards are even rarer than rare cards, and they are usually used to provide more unique and niche attack patterns. These cards are generally very useful and can be used to great effect if they are incorporated into a deck correctly. However, they are also much harder to level up and may require a significant investment of time or resources to obtain. Alongside their more unique background in the Clash Universe, this rarity can be associated with the color purple.

Legendary Cards

Legendary cards used to be the rarest cards in Clash Royale, making them also the most worshipped rarity back in the day. These cards are usually released to introduce never before seen mechanics for everyone to play around with, such as the Princess' long range, Bandit's immunity dash, and the Phoenix's revival mechanic. They are often very difficult to come by and often require the most meticulous card management when being upgraded. This rarity can be associated with the color scheme rainbow.

Champion Cards

The newly introduced rarity comes along with a special ability that can be activated with additional elixir. These cards often have higher stats and more absurd mechanics compared to other rarities which makes them the most superior rarity. Despite its capability to shorten the cycle of your deck as long as the champion is alive, its broken mechanics only allows the player to put one Champion on a deck so choosing a Champion to add on your deck will define what deck and playstyle you want to invest in. This rarity can be associated with the color gold and its catchy two-word naming scheme.

Card Evolution

Not entirely a new rarity, but a new mechanic was introduced wherein cards can now evolve (if applicable) when it is unlocked through evolution shards. Not only does the card have better stats and groundbreaking abilities, but also it's visuals are improved and complemented with a glowing indigo theme showing that the card is evolved. Note that just like the champion rarities, two evolved cards at maximum can only be fitted per deck and it also has it's own cycle in order for the evolved card to be placed. A trend can be observed where the cycle depends on how low or high the card's elixir cost is in order for the evolutions to balance each other out. The lower the elixir cost, the higher its cycle turns are. When cards evolve, they become associated with a diamond shape and a glowing color of indigo which symbolizes the presence of dark elixir.

Card Types

Troops

Troops are cards that roam around the arena and are capable of attacking various entities. Some only focus on buildings which are known as win conditions. Most troops can also attack their fellow troops; some towards ground troops, and some also capable handling air. Each troop has its own unique stats and gimmick. For example, a Baby Dragon is a moderate HP tank that flies and deals AoE damage. While Skeleton Dragons are two flying dragons that deal double the damage, but are more fragile compared to the Baby Dragon. There are no viable decks that do not contain troops since it is an integral part of deck building.

Spells

Spells are cards that are able to support cards from all over the arena. Depending on what spell is used, they can be versatile in different situations which sometimes reverses the tides of battle. Some spells are able to damage troops and buildings, some are only used to support troops, some summon troops, while some can excel when used defensively. Choosing the right spell to put in your deck will boost your chances in winning. Although some viable decks do not rely mainly on spells in order to excel competitively.

Buildings

Buildings are cards that can only be played on your side of the arena. Each building can be used defensively which allows positive elixir trades to happen when placed correctly. Some buildings like Mortar and X-Bow are more focused on the offense and are considered win conditions since they are able to attack enemy towers while staying on your side of the arena. Depending on the archetype, some buildings are mostly seen on cycle decks while some beatdown decks use buildings that are more focused towards elixir investment.

Tower Troops

A newly-added component of any deck, which would technically be the ninth (9th) card of your deck. Originally, Tower Troops weren't introduced and by default, your Crown Tower only contains a Tower Princess which usually gives them the name "Princess Towers". But with the new concept, your two Crown Towers can now contain different troops with differing attack patterns and stats dynamically changing interactions between cards and towers. Tower Troops have also been introduced as their own type of card; their card visuals resembling a castle (battlement), also allowing them to be also split into card rarities.

Working With Card Types and Rarities

With multiple card types and rarities having the potential to be chosen as parts of your deck, it is important to consider the benefits of practicing variety and balance with what you prioritize on placing on your deck. As a free-to-play (F2P), it is also advisable to know which cards are the most impactful to upgrade. For Rarities, Common cards are the easiest to upgrade and Champion cards are the most tedious to upgrade. For Card Types, Troops such as Win Conditions and Damage Dealers should be upgraded first, followed by Spells that complement them. As you continue upgrading cards at this order, crafting decks with decently levelled cards from your card selection should bring more ease.

Despite what was described earlier about rarities, there are certain arguments one can derive about how the entire concept of Rarities haven't been followed or relevant as of late. It should also convince you how Rarities have been balanced out as time passes.

DisfunctionallyFunctional's video points out the indistinguishable nature of cards despite its corresponding rarities:

It is important to balance out your deck with multiple card rarities and types since not only does it allow you to utilize varying potentials of the cards' mechanics but it also lets you be more efficient on allocating your resources on different kinds of cards. It is best to be wise when choosing a deck with cards that are not redundant. It is not mandatory but it is a good rule of thumb when creating decks while progressing.