Eerie is an ability word, which means it doesnt have a strict rules definition, but instead ties together lots of similar cards
Reflecting Pool In almost every deck I own with two or more colors, Reflecting Pool is basically an untapped dual or tri-land
They require you to go five turns without taking damage (or proliferate their filibuster counters), but there are many ways in blue and white that can keep you clear from danger, like Magus of the Moat, fogs, and Ghostly Prison effects
Bucking the trend of understatted Spirits in Kamigawa block, this beatstick promised six damage a turn for well below the accepted rate of the day
If youre playing a bunch of effects where the Ring tempts you, then this can become a bonkers card-drawing engine