From time to time, Special Event Challenges will appear on the player's Tournament tab. Special Event Challenges are similar to Classic and Grand Victory Challenges, offering similar rewards and having similar rules while also possessing a similar matchmaking system separate from ladder play. However, special event challenges have certain special conditions and can have one-time rewards which can be won by reaching certain win counts for the first time in that challenge. If the Special Event Challenge ends and your current challenge attempt has not yet reached the maximum number of wins or 3 losses, you will be given the prize of your current number of wins.
Special Event Challenges can be classified with a number of parameters. Theoretically, these parameters can be played at any combination.
By number of players:
- 1v1: Each side has one player.
- 2v2: Each side has two players. Players can team up with either a random player, or a clanmate.
By Deck size:
- Default: Each Deck has 8 Cards.
- Mega Deck Challenge: Each Deck has 18 Cards.
- Default: Destroying the opponent's Crown Towers.
- Touchdown Challenge: Reaching the opponent's End Zone with any troop.
- Heist Challenge: Destroying the opponent's Safe.
By wins and losses:
- Default: Eliminated after three losses, and can continue by paying Gems in some of these Challenges. The total amount of wins vary widely, from 3 to 20. The 3 to 6 win Challenges usually have no free entries and are for gaining small stacks of certain non-Legendary Cards, while the 20 win Challenges are for CRL qualification.
- Practice: Losses are not counted, and the players aim to accumulate either a certain number of wins or a certain number of Crowns.
By Elixir rate:
- Default: Elixir is gained at normal rate.
- Double Elixir Challenge: A challenge in which Elixir generates at two times the normal speed throughout the whole match. However, players start with 0 Elixir instead of 5. Crown Towers have a skin that resembles the Elixir Collector.
- Triple Elixir Challenge: Similar to the Double Elixir Challenge, but Elixir generation rate is triple the normal rate throughout the match.
- Ramp Up Challenge: Elixir generation rate is normal at the first minute, double at the second minute, and triple from the third minute onward.
- Sudden Death Challenge: The game starts with 3 seconds left of normal time and then proceeds into a 3-minute Overtime. The match begins with double Elixir generation since it starts in the last few seconds of normal time. The player who gets the first Crown wins, similar to Overtime in normal battles.
- Default: No special environment.
- Rage Challenge: All Troops and Buildings are in the effect of Rage. Elixir generation is 1.35x normal as well. This Rage environment can be stacked with Rage card or the Lumberjack's dropped Rage additively (1.7x normal).
- (Troop Rush): A certain type of troop is generated by the system for both sides.
- (Treasure Hunt): A "Treasure Building" lies at the center of the Arena. It does not belong to either side, and has two health bars, one for each side. Both sides race to deplete the health bars to get the treasure for their own side.
- Elixir Capture: There is an Elixir Storage building with 2120 health. When destroyed, it gives 2 Elixir. Elixir also appears on the bridges that can be collected by troops, awarding the player 1 elixir (some troops, such as the bandit while dashing or barbarian barrel while rolling will not collect these).
- Dragon Hunt: "Treasure Building" is an Elixir Egg that gives a random Dragon troop. This mode could be a reference to the phrase "Easter Egg".
By Decks used:
- Default: Uses player's own battle decks, and players cannot use Cards they have not unlocked yet. Cards under the Challenge/Tournament's cap are not adjusted up to this level, and players use their own Card levels if played in Clan Wars Collection Day mode.
- Restricted Card Challenge: A challenge in which players get to build a deck restricted to certain subsets of cards in the game, for example:
- Retro Royale Challenge: A challenge in which players build decks exclusively with cards that were available before a certain date.
- Modern Royale Challenge: A challenge in which players build decks exclusively with cards released after a certain date.
- Arena Challenge: A challenge in which players build decks exclusively with cards unlocked at or below a certain Arena. Note that at the highest Arena, this becomes a Default Challenge: players use own decks.
- (Special Theme Challenge): A challenge in which players build decks exclusively with cards of a certain theme.
- Mini Collection: Each player is generated a subset of Cards. In this mode, different players may have different subsets of Cards.
Modes listed below do not use player's battle decks, Cards under Tournament Standard (level 9) are adjusted up to this level, players can use Cards they have not unlocked yet, and all Cards are also adjusted to Tournament Standard if played in Clan Wars Collection Day mode.
- Draft Challenge: A challenge in which players are given a choice between two Cards and gets to keep one while giving the other to his/her opponent. Each player picks half the deck size of Cards. If a card is featured, one of the players will be guaranteed to get that card.
- Built Decks Challenge: A challenge in which pre-built decks are given at random to each player. "Classic Decks Challenge" belongs to this mode.
- Locked Card Challenge: A challenge in which players get to build a deck with any card in the game but have to use a specific card that is locked in the first slot. The player wins the featured card, often through one-time rewards.
- Mirror Challenge: Both players have the same random deck and have the same initial deck rotation. It also features the Mirror card, making the word "Mirror" a double entendre.
Some combinations have special rules:
- In 2v2 Draft Challenges, player Blue 1 and player Red 1 pick cards for each other, and so do player Blue 2 and player Red 2. If the Challenge has a featured card, it will be guaranteed to appear in both pairs of opposing players and will end up being contained in two player's decks. Players of the same team can see each other's card picking process, and one player can wait a few seconds to see his teammate's choice before making his own choice, in order to get a better card combination and/or to prevent the opposing team from doing so.
- In 2v2 Mirror Challenges, player Blue 1 and player Red 1 get the same deck with the same initial deck rotation, and so do player Blue 2 and player Red 2. All four players have the Mirror card in the deck.
- Special Event Challenges were introduced in the November 2016 Update.
- The March 2017 Update added one-time rewards to Special Event Challenges.
- The December 2018 Update added the option to continue after getting three losses in certain Special Event Challenges.