A lot of hydras are very efficient at their mana value and a lot of them have X in their cost which scales with the game or allows you to spend more mana on their activated abilities
Final Iteration Creature Eldrazi Insect Flying Wizards you control get +2/+1 and have flying
Commanders Sphere Commanders Sphere is the steady, dependable type of mana rock
It was after my second game with Yarok, where I assembled infinite mana in barely any time with Deadeye Navigator/Peregrine Drake and cast Villainous Wealth for X = 1,000,000, that my friend observed: Wow, its almost like getting two triggers for every enters-the-battlefield effect is broken. And they were right
This card continues its climb into the mid-20s, but with such a big shift changing the landscape of holo and reverse holo versions, there's no guarantee of where this card may go