Hey fellow Planeswalkers! When it comes to deck-building in Magic: The Gathering Arena, focus on a clear strategy. Choose cards that work well together and support your game plan. Make sure to have a good balance between creatures, spells, and lands. Don’t forget to include some removal and card draw to handle different situations. And always playtest your deck to see how it performs and make adjustments as needed. Happy crafting and may your opening hand always be in your favor!