how rare are promo cards Pokemon Card - Black Star #1 - Pikachu Is there value in these

It is just a sideboard card, of course, but one of the best ones ever printed

Adaptation Deviation: In the anime, Number C1000: Numerounius had an original ATK of 10,000 (and a measly original DEF of 1,000), and Number iC1000: Numerounius Numeronia's original ATK and DEF were both 100,000

Then, just for Summoning it, you get to search out a Tachyon Spell or Trap from the deck

Maybe I would call them unofficial Pokemon cards or licensed non-TCG Pokemon cards, but Pokemon cards to me means officially released under the company that owns the property

Of course, the first one could just be a removal spell to squish the frog, but you might even draw off that one