Let's take a look and see what X spells I like the best for a Zaxara build
Dominaria United Draft Boosters contain: 1 Rare or mythic rare that can be a legendary creature and/or showcase stained-glass, borderless, or Phyrexian-language card 1 Rare or uncommon legendary creature with an opportunity to get the showcase stained-glass, borderless, or Phyrexian-language treatment 1 Basic land, which can have the showcase stained-glass treatment 1 Basic land or non-foil common, or an opportunity for many other cards, including a traditional foil that could be rare or mythic rare, showcase, borderless, or Phyrexian 2 Nonlegendary uncommons 9 Commons Commander Decks Our return to our most legendary plane meant that we had to do something extra special for our Commander decks
All six included in Disney100 Collectors Edition boxes
A word can be a single letter
Of course, this is also on the Reserved List
They dont go away as steps, phases, and turns end, and effects that add mana of any type cant give you energy counters