Like most Magic: The Gathering cards, the value of Circle of Protection: Artifacts 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 (Fifth Dawn)
Just getting something with a useful energy ETB is often enough to really start rolling, as even copying a Conduit Goblin nets you 4 energy
As far as hydra lords go reducing the cost of your important spells by 4 mana is a big incentive
[52] The two Maximum Monsters destroyed each other at the same time, much to Luke's horror, and he desperately tried to gather the scattered fragments of the cards
These games are more sought after than ever as Nintendo shut down the 3DS and Wii U eShops in March 2023, meaning the only way to play Pokmon Red, Gold, and so on is on their original Game Boy and Game Boy Color consoles