@Nikki
To be honest, it's just a small 1v1 moba card game (that's what it is however saying it doesn't make too much sense imo). Whoever can push down towers better and defend against their opponents push better. Not only that but it has an elo system and different ranks based on how many trophies you have, (you earn trophies by winning duels).
There are also Clans, which for the most part are useless other than being a medium for socializing and earning more cards (every few hours you can request your clan to give you extra cards they have 10 commons or 1 rare per request. Another incentive clans offer are the availability to challenge friends or clan mates to duels - 1v1's.
At the very heart of the game you have the cards you are given which for the most part are based off the popular game Clash of Clans. Each card has a cost of elixir that must be used in order to play it. At the beginning of a duel you are given 5 elixir and game 1 each second. The way you use your elixir and make plays great decides the overall outcome. Playing the right cards that can counter theirs while using less elixir is known as elixir advantage and as mentioned before greatly plays a role. An example would be, player 1 uses a Prince which costs 5 elixir to use to try and take out a tower player 2 times the placement of the Prince and counters with the card Skeleton Army which only costs 4 elixir. Because player 2 used a card with a lower elixir cost than player 1, player 2 has the elixir advantage and can play more cards now versus player 1 who used more elixir to play a better card. At first this may not seem too important but the higher you begin to climb the more costly cards will begin to be and it will matter.
Now the main goal of a duel and how to win. Well it's quite simple, take down the towers. There are 3 towers, two crown towers and the kings tower. Each Crown Tower is worth 1 crown and the King's Tower automatically wins the duel if you manage to take it down (however I have had a draw since my opponent and I both took down each persons King's Tower at the same time). You get 3 minutes, I believe, to try and take down at least 1 tower. However if you and your opponent have the same amount of towers up when the initial 3 minutes are up it goes into overtime and the first to take down a tower wins the duel. Although, if either player fails to take out another tower the duel ends in a draw.
TL;DR
Spoiler: Take down the opponents towers to win with the cards supplied to you from your deck.
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