Gastrodon is card #29 of 114 in Steam Siege (2016), a Rare illustrated by Aya Kusube. At about $0.84 it is the #38 most valuable card in the set. In a Steam Siege booster it turns up about once every 42 packs. It is one of 8 Gastrodon cards printed so far.
2007Secret Wonders
2009Rising Rivals
2016Steam Siege
2017Crimson Invasion
2022Lost Origin
2024Surging Sparks

















See the full Steam Siege card list
An ungraded Gastrodon from Steam Siege sells for about $0.84. A PSA 10 is worth more, roughly $4.20 by our estimate, and a PSA 9 around $1.93.
It is a Rare, and it shows up about once every 42 Steam Siege packs.
Aya Kusube drew the art for this card.
Yes, as a digital simulator. Holobrook lets you open Steam Siege booster packs in your browser with the set's real pull rates and keep what you pull in a digital binder. No real cards, nothing to buy.