He gives you a favorable trade against certain commonly used characters like Madam Mim Fox
Whos to say the same cant happen again
Age-Graced Chapel Arcane Sanctum Ballroom Bleachbone Verge Caves of Koilos Concealed Courtyard Contaminated Landscape Crystal Quarry Deceptive Landscape Desolate Mire Dromar's Cavern Eclipsed Steppe Fetid Heath Fisk Tower Foot Headquarters Forlorn Flats Forsaken Sanctuary Forum of Amity Godless Shrine Goldmire Bridge Great Hall of Starnheim Indatha Triome Insomnia, Crown City Isolated Chapel Misty Palms Oasis Murmuring Bosk Neglected Manor Nomad Outpost Orzhov Basilica Orzhov Guildgate Raffine's Tower Restless Fortress Salt Flats Sandsteppe Citadel Savai Triome Scoured Barrens Scrubland Shadowy Backstreet Shambling Vent Shattered Landscape Shattered Sanctum Shineshadow Snarl Silent Clearing Silverquill Campus Snowfield Sinkhole Starlit Sanctum Sunlit Marsh Tainted Field Temple of Silence The World Tree Tomb of the Dusk Rose Tournament Grounds Turbulent Moor Umbral Expanse Vault of Champions Vault of the Archangel Wizards' School

Cards without this mark are either shadowless or unlimited editions, which, while rare, are less valuable
Conclusion As I mentioned in the intro, this is my experience with the Arena economy as someone who needs most of the cards in a set right away, plays primarily constructed with both Standard and Historic, and doesn't really have the ability to pay for cards with hours and hours of my time rather than with actual money
Since its a Stage 2 Pokmon, youll want to use Professors Research, Pok Ball, May, and Rare Candy to accelerate the process