Some cards reward a closer look. Entei is one of the pokemon that quietly appears in the background of 2 other cards, painted by Ryo Ueda and Kouki Saitou.
Of the 2 cards, HS—Undaunted contributes the largest cluster. The illustrator most often responsible is Ryo Ueda, whose Entei cameos appear in 1 of these cards.
2 cards with Entei in the background spanning 2005–2010, with art by Ryo Ueda and Kouki Saitou.
Entei appears as a background cameo across 2 Pokémon cards.
These appearances range from clear sightings to barely-visible silhouettes, scattered across 2005–2010 of the TCG.
Each cameo rewards collectors who pause to look closely at the card art.