Like most Magic: The Gathering cards, the value of Double-Faced Substitute Card depends on a few consistent factors: its rarity, the printing and finish (regular or foil), its physical condition, and the set it was printed in (Kamigawa: Neon Dynasty Substitute Cards)
This is a card that a lot of Commanders want, but its still a pretty specific effect compared to true Commander homestays, so demand should vary
Two shiny black stars: Ultra Rare
Bright, consistent light source Optional The magnifying glass I use has a built-in light but having a high output light is good for looking at the holo and surface of a card from multiple angles to catch flaws
If you compare this illustration with the Suicune in this same set, for instance, the difference is jarring