Like most Pokmon cards, the value of Shellder depends on a few consistent factors: its rarity, the printing and finish (regular or foil), its physical condition, and the set it was printed in (BREAKpoint)
Each Prerelease Pack contains the following: 5 Magic: The Gathering | Avatar: The Last Airbender Play Boosters 1 Seeded Magic: The Gathering | Avatar: The Last Airbender Character Booster Each Character Booster is themed around a different Avatar: The Last Airbender character and a Magic color
Then in War of the Spark not only did they print a whole slew at rare, but uncommon planeswalkers, multicolor walkers and colorless planeswalkers were popping out of packs left, right, and center
Again, it is the cheapness of the card that makes the limper life offerings that much less important
Hold it up to a bright light, and if you can see through it, its probably fake