how to identify pokemon cards tell if are real? I found these online very cheap (suspiciously low), not sure what the going rates are but didn't know how to verify. : r/PokemonTCG how to spot fake base

You can test your luck with opening randomized booster packs as well as purchase or trade for single cards that you need to complete your deck

If you somehow control two copies of Gandalf the White, a legendary permanent or an artifact entering or leaving the battlefield causes abilities to trigger three times, not four

It might make the deck more powerful but it also makes it less consistent

Some local stores will do a sealed tournament where players get six sealed booster packs of the latest set and use it to construct a 40-card deck

It's worth checking out TCGPlayer if all else fails, though bear in mind that these items are sold by third parties so will likely be overpriced