all ditto pokemon cards | EX Delta Species after cards of today. Ditto EX Delta Species |

It also has a free switch in with its ability, which is not strictly necessary but a nice addition nonetheless

Then came the experimental E-Card and early EX series

[6] Shadowless cards are still considered valuable since they were part of a smaller print run

Pokemon - Mewtwo (10) - Base Set 2 - Holo

Since the commemorative box set was only sold for a limited time, and there were strict purchase limits, there are a limited number of these promo cards in circulation

Blemishes, bends, scratches, and stains on cards reduce their value, so its best to send them into a card verification service like CGC Cards to receive an official grade