Dataminer reveals upcoming features and contents in Clash Royale including the new level of rarity called Hero, unused troops (not included in the upcoming 4 cards) and brand new challenges. Here's everything we know so far.

Hero Cards

A dataminer has unveiled a new rarity of cards which appears to be better than the current Legendary cards. The new rarity is called Hero cards but as for the moment, the cards have the same stats as the usual common cards. But it's important to note that the dataminer has dug a new feature called "abilities" which seem to be connected with the Hero cards meaning Supercell may soon introduce activable abilities in the game - much like the Barbarian King and Archer Queen on Clash of Clans perhaps?

Unused Troops

The unused troops have yet to be named but some details were already present. Here's the full chart about the two "unused troop."

Clash Royale New Challenges

Three Bridges - A brand new challenge where we will see a new bridge at the middle! 5 gems, prizes are identical to classic challenge.
Crown Duel - referred in the game files as Draft Mode.
Hero Challenge - 100 gems, prizes are the same as the grand challenge. No Free Entry.
Electro Wizard Challenge - "Build a deck with the Electro Wizard; all cards are available in this special challenge.Each win increases your prize; at 12 wins you receive the top prize AND the Electro Wizard!"

Misc

Friendly Battles - You will now be able to play Double Elixir Mode, Draft Mode and Blind Deck Mode with your friends.
Chest - Unlocking chest with gems now costs less.
Titan Arena Layout File -  "With a private server we can probably see how it is (nearly empty for now)

That's it for now guys! We will update this article for any future leaks so be sure to check it out! What do you think of the datamined secrets? Leave your thoughts in the comments down below!