How to tell them apart

First Edition cards carry a small "1st Edition" stamp, usually to the left of the artwork. Shadowless cards (an early Base Set printing) lack the drop shadow on the art box. Unlimited cards have the shadow and no stamp, and are the most common.

Why it changes the value

First Edition and Shadowless printings were produced in far smaller quantities, so they are scarcer and command large premiums over Unlimited copies of the same card — especially in high grades.

Value the exact printing

Because the same card can be worth wildly different amounts by printing and grade, identify yours precisely. Slabline values Pokémon cards from real comps at the exact grade, so the number reflects the printing you actually own.