Trevenant & Dusknoir-GX is card #SM217 of 248 in SM Black Star Promos (2017), a Promo illustrated by Mitsuhiro Arita. At about $34.31 it is the #45 most valuable card in the set. It is one of 18 Dusknoir cards printed so far.
2007Diamond & Pearl
2009Supreme Victors
2012Boundaries Crossed
2014Flashfire
2017Burning Shadows
2020Vivid Voltage
2022Brilliant Stars
2025Prismatic Evolutions

















See the full SM Black Star Promos card list
An ungraded Trevenant & Dusknoir-GX from SM Black Star Promos sells for about $34.31. A PSA 10 is worth more, roughly $172 by our estimate, and a PSA 9 around $78.91.
It is a Promo.
Mitsuhiro Arita drew the art for this card.