
XY·Released Aug 3, 2016 (10.1 yrs)·116 cards
Stage: No longer being printed by TPCi — remaining supply is on the secondary market.
Across 10 tracked SKUs in the Steam Siege set, the Battle Arena Decks: Keldeo EX vs Rayquaza EX leads over 90 days at +61.3%, while the Steam Siege Prerelease Kit lags at -9.7%. Median 90-day move across the set: +7.0%.
Sealed Steam Siege sits past or near the end of its print window, so supply pressure is light.
A XY-era set. Released 10.1 years ago and past the typical print run, so remaining sealed supply is whatever is already out.
| Product | Type | Price | 30d |
|---|---|---|---|
| other | $161.64 | ↑+7.6% | |
| other | $103.96 | +0.0% | |
| other | $94.95 | +0.0% | |
| other | $71.99 | ↑+1.4% | |
Top 10 cards by current raw market price. These feed the Open-vs-Hold EV calculator on booster-box pages.

Gardevoir EX (Secret)
$84.22

M Gardevoir EX (Full Art)
$48.62

Volcanion EX (Secret)
$33.53

Other sets in the XY series.
| Box |
| $1,262.50 |
| ↑+7.2% |
| other | $160.32 | ↓-2.2% |
| other | $36.07 | ↑+6.0% |
| other | $63.73 | +0.0% |
| other | $20.07 | ↑+1.9% |
| other | $22.91 | ↓-5.0% |
M Steelix EX (Full Art)
$26.06

M Gardevoir EX
$20.33

Gardevoir EX (Full Art)
$20.22

Steelix EX (Full Art)
$18.52

M Steelix EX
$10.88

Professor Sycamore
$9.40

Volcanion EX (Full Art)
$8.49
Raw (ungraded) market prices. Methodology