It obviously went on to be a giant hit without causing major problems so I guess you could call it an accident with a happy ending
Its value depends on the exact card, variant, visible wear, and buyer trust
Whats harder to predict is whether any of the potential Combo/Reanimator style decks will rise to consistently challenge the dominant Midrange and Aggro piles
The original starter Pokemon pretty much dominate this list, and rightfully so
It has the ability to be aggressive and prevent healing
Generally, there is the primary Cube, the worth-the-Limited-splash-big-stuff Chromatic Cube and a supplemental combo-based one, the Tinkerer's Cube. MTG Online (MTGA's much-maligned step-sibling) has Cube on the regular if you find that you really love Cube