One sale can move a card by thousands. Four cards that show how
Blue-Eyes Dark Duel Stories went from $3,000 to $1,250 on one sale. Here is how to tell a real move from a missing one.
A market price is an average of recent sales. For most cards that is dozens of sales a week, and the number moves smoothly. For rare cards it can be one sale every few months, and then the price is simply whatever the last buyer paid. These four cards show what that looks like, and why a big percentage on a rare card often means much less than it seems.
Blue-Eyes White Dragon (Dark Duel Stories): five price changes in a year
The Blue-Eyes White Dragon promo from the Game Boy game changed price five times in 2026. It sat at $3,000 from April to August, dropped to $1,250.24 on August 10, then moved to $1,337.92 and $1,450.56 within two weeks, and has not changed since.
Read as a chart, that looks like a crash. In reality, a few copies changed hands at very different prices. The cheapest listing today is $1,600.98, above the market price. In 2024 the market price even showed $100 for a while, when every listing was above $1,600: a sale of a damaged or mislisted copy can set the number for months.
Celebi Star: doubled for two days
Celebi Star from EX Crystal Guardians sat at $750 from July. On October 18 it jumped to $1,375, and on October 20 it was back at $750. One sale appeared and dropped out of the average again. Anyone who saw the price on October 18 saw a card that had "gained 83%". It had not.
Sabo (SP): no sale since August
Sabo (SP) from the One Piece Anime 25th Collection has shown $1,125 since August 5. That is not a stable price. It is the last sale, eleven weeks old, while sellers keep moving their asking prices. The cheapest listing has gone from $1,750 in July to $1,300 on October 25.
Boa Hancock (SP): the last sale is above every listing
Boa Hancock (SP) has shown $1,421.01 since September 1. Meanwhile the cheapest listing fell to $969.99. If you wanted one today, you would pay a third less than the "market price" says.
How to read a price on a rare card
- Look at the shape of the chart. Long flat lines broken by steps mean single sales. A smooth line means a real market.
- Compare with the cheapest listing. If the market price sits far above or below what you can actually buy for, the last sale is stale.
- Check how often it changes. A card that moved five times in a year has no "today's price", only a last price.
- Distrust big percentages on rare cards. +83% or −58% on a card that sells twice a year is one buyer, not a market.
On tcgrate, a market price that sits far below every listing is marked as stale and kept out of our movers and rankings. We also learned this the hard way: a few of our own early videos used numbers like these, and readers rightly called them out.