plusle pokemon card 6/12 Holo Rare (Swirl) LP QDD-3KY-MLG Common Card Type Plusle - 065/062 - SV3a:

You may cast an instant or sorcery spell with mana value X or less from among them without paying its mana cost

Her strength lies in her attack trigger, where you exile the top five cards of your library and may cast an artifact from among them, which also gains affinity for artifacts

This being said, Alpine Moon does provide an answer if you are really struggling to beat the sac Deserts, the flip enchantment lands like Search for Azcanta and Arguel's Blood Fast, or the Memorial to Folly cycle

Risen Executioner: 4-drop Zombie lord with a worthy grveyard effect

I have built all three decks to be under $100 in budget