Every week, the Clash Royale developers release new challenges to help players earn additional resources, gems, and other magic items. The latest of these challenges is Mega Deck, a unique challenge where gamers must use 18 cards to fight in 1v1 battles.They must choose the top 18 cards from the available unlocked cards list. A good 18-cards deck must have defensive and attacking cards, mini tanks, anti-air cards, etc.Five most potent cards for Mega Deck challenge in Clash Royale5) FishermanFisherman is a Legendary card (Image via Sportskeeda)Cost: 3 ElixirDamage: 256Hitpoints: 1152Fisherman is one of Clash Royale's most powerful Legendary cards and can be obtained using Legendary Chests and tokens in Arena 15. He's a melee unit with a lot of damage, but he can only attack one victim at a time.Fisherman can use a hook to entangle enemy troops and drag them towards him. Users can use it to get opposing troops to attack the King Tower and take out the cannon for defense.4) FireballFireball is a great spell card (Image via Sportskeeda)Cost: 4 ElixirDamage: 913It's one of the best spell cards in Clash Royale, and it's only available if players have completed the in-game training. This card is ideal for stopping an enemy's aggressive push because it can provide massive area damage to the enemy's troops and towers at a fair range.Gamers can use the Fireball card against Musketeers and Wizard cards.3) WitchClash Royale@ClashRoyaleWho's your favourite Witch? 🦇 5:30 AM · Jul 13, 2021252866Who's your favourite Witch? 🦇 💀 🐷 https://t.co/WtfpBJzmK5Cost: 5 ElixirDamage: 178Hitpoints: 1110Once users reach Arena 5, they can unlock the Witch, an Epic card. She is a high-damage, high-hitpoint unit that deals area damage. Every seven seconds, the Witch generates four miniature skeletal troops while causing damage to opposing troops and towers.She has an excellent anti-air card that should be combined with high-hitpoint cards such as Prince, Mega Knight, and Pekka.2) PekkaPekka is a powerful Epic card (Image via Sportskeeda)Cost: 7 ElixirDamage: 1081Hitpoints: 4982Pekka is one of the most potent Epic cards. It's excellent for use as a hard-hitting tank because it's a melee ground unit with great damage and hitpoints.It's a wonderful pick for many gamers because it can deal lots of damage. Low-elixir support units such as Goblins, Bats, and the Skeleton Army should use it.1) Mega KnightClash Royale@ClashRoyaleHow to: Mega Knight. Watch here: youtu.be/SaVYbFuszUA5:30 AM · Aug 26, 201754549How to: Mega Knight. Watch here: youtu.be/SaVYbFuszUACost: 7 ElixirDamage: 355Hitpoints: 5280In Clash Royale, Mega Knight is a Legendary card that users can unlock once they reach Arena 7. Like other splash damage cards in the game, it deals enormous damage when utilized.Mega Knight is one of the game's most powerful cards, with high hitpoints and damage. Players should deploy support troops such as Wizards, Bats, and Musketeers with this card.Note: This article reflects the author's views.