Gengar

Gengar (13/165), the Holo Rare from Expedition Base Set, has an estimated ungraded market price of about $725, typically in the $630–$820 range. Note: 23 other cards named Gengar exist across the sets Riffle tracks, at very different values; check the collector number.

This page covers Gengar (13/165), the Holo Rare (about $630–$820) from Expedition Base Set.

The other versions: #94/102 from Triumphant (Rare PRIME, about $500–$640); #10/144 from Skyridge (Rare, about $440–$580); #H09/144 from Skyridge (Holo Rare, about $195–$260); #5/62 from Fossil (Rare, about $190–$250); #11/110 from Legendary Collection (Holo Rare, about $155–$210); #48/165 from Expedition Base Set (Rare, about $150–$200); #5/92 from Legend Maker (Rare, about $140–$180); #27/130 from Diamond & Pearl (Rare, about $70–$95); #17/99 from Arceus (Rare, about $55–$75); #18/100 from Stormfront (Rare, about $55–$75); #16/99 from Arceus (Rare, about $38–$49); #TG06/30 from Lost Origin Trainer Gallery (Rare, about $37–$48); #60/162 from BREAKthrough (Rare, about $36–$47); #20/62 from Fossil (Rare, about $35–$46); #35/83 from Generations (Rare, about $35–$46); #38/111 from Crimson Invasion (Rare, about $21–$28); #70/214 from Unbroken Bonds (Rare, about $20–$27); #85/202 from Sword & Shield (Holo Rare, about $7–$9); #57/198 from Chilling Reign (Holo Rare, about $4–$6); #066/196 from Lost Origin (Holo Rare, about $3–$5); #094/165 from 151 (Rare, about $3–$4); #050/88 from Perfect Order (Rare, about under $1); #057/91 from Paldean Fates (Uncommon, about under $1).

The collector number printed at the bottom of the card is the reliable way to tell them apart.