You can then tap the Crucible and remove storage counters to gain that much mana in any combination of colors - solely for casting Dragon spells or activating Dragon abilities
First introduced in Wilds of Eldraine, the Adventure mechanic allows players to cast the Adventure half of a card, then later cast the other half from exile once the Adventure resolves
Other cards that can fetch very high prices include the remaining Power Nine (Mox Pearl, Mox Sapphire, Mox Jet, Mox Ruby, and Mox Emerald, Time Walk, Timetwister, Ancestral Recall) as well as a selection of cards from 1993 and 1994
These two icons of Cybertron are Reversible, meaning both sides of each card have the same rules text but different art, allowing you to choose their look as they enter the fray