Hey fellow planeswalkers! When it comes to deck-building in Magic: The Gathering Arena, always remember to have a clear game plan in mind. Focus on a theme or strategy that your deck will revolve around. Whether it’s aggro, control, or combo, make sure your cards work together towards a common goal. Also, don’t forget to fine-tune your mana curve to ensure a smooth gameplay experience. And most importantly, playtest your deck frequently to make necessary adjustments. Happy brewing!