Union Arena's Attack on Titan release arrived during a resurgence of anime TCG popularity in the West, positioning itself alongside established properties in a competitive market. The 2025 set captured momentum from both longtime franchise fans and newer collectors drawn to the accessible Union Arena system, which emphasizes accessible gameplay and striking character artwork over rarity-driven complexity. Annie Leonhart's Female Titan form stands as one of the set's most iconic character representations. Her Super Rare designation reflects her significance within the series, and collectors gravitate toward cards depicting her transformation sequences—moments that define the narrative and remain visually striking across different card treatments.