One of the reasons for that was a lack of support, with few stores actually running the Duelist League events, despite the involvement of big retail names such as Toys R Us
Pay attention to how your deck performs in different situations
Eradicator Valkyrie - Your opponents are gonna hate this, and it might not last long
That means you kind of want a deck full of pump spells or Equipment, plus casting from exile enablers, in order to whack one thing pretty solidly each turn
Fusion Strike, Silver Tempest, Chilling Reign, Crown Zenith, Brilliant Stars, Chilling Reign Shining Fates, Vivid Voltage, Rebel Clash, Battlestyles, Astral Radiance, Lost Origin, Darkness Ablaze, Evolving Skies, Fusion Strike, Crown Zenith, Lost Origin, Shining Fates, Paldean Fates, 151, Ultra Prism, Hidden Fates, Evolutions, burning shadows, sun and moon base, guardians rising, crimson invasion, steam siege, forbidden light, cosmic eclipse, breakpoint, breakthrough, Sun and Moon sets, XY sets