best rare cards to upgrade clash royale Top 5 for EVERY Rarity in 4 CARDS that should be

18% growth

Everyone starts by flipping over the top card of their deck simultaneously and repeating this until they either drop out or draw two Dark Omens and bust, amassing money to buy more soldiers and gold to pad out your deck, Swords to win you the rounds Victory Points, and champions with various effects and Sword values

On top of that, its also very powerful, which is the ideal combination as far as Im concerned

Akroma's Vengeance Austere Command Avenge Blood Money Blood on the Snow Bontu's Last Reckoning Breaking Point Catastrophe Ceaseless Conflict Citywide Bust Cleanse Cleansing Nova Cloud's Limit Break Crux of Fate Damnation Damning Verdict Day of Judgment Deadly Cover-Up Deadly Tempest Deadly Vanity Death Begets Life Decree of Annihilation Decree of Pain Depopulate Devastation Do or Die Don't Move Doomskar Dusk // Dawn End Hostilities Endemic Plague Expel the Interlopers Extinction Extinguish All Hope Fated Clash Fated Retribution Fell the Mighty Fight to the Death Final Act Final Showdown Force of Despair Forced March Fumigate Game Over Gaze of the Gorgon Glyph of Doom Glyph of Reincarnation Guan Yu's 1,000-Li March Harsh Mercy Hellfire Hour of Reckoning In Garruk's Wake Jokulhaups Kaya's Wrath Kindred Dominance Kirtar's Wrath Life's Finale Localized Destruction Mandate of Abaddon March of Souls Martial Coup Mass Calcify Mogg Infestation Nature's Ruin Necromantic Selection No Witnesses Obliterate Organic Extinction Overwhelming Forces Path of Peril Perish