There does not seem to be any indication that any one of these cards is more rare than the other but based on early eBay prices, the Shiny/foil version of Pikachu seems most desirable
This deck all about X costs in cards, and Hydras happen to be the best Magic creatures in these colors for X
In Modern Dredge, its the only way to return Prized Amalgam without any further restrictions
You can help ensure Simon only draws only you a card you can include Barbarian Class or Wyll, Blade of Frontiers to roll an extra dice and ignore the lower one
Edgar is quite competitive at the high levels of Commander play, but here Im aiming to leave the power level lower on the spectrum, as a slightly upgraded precon deck
Based on secondary market data from platforms like TCGPlayer, serialized cards often command a 500% to 1,000% premium over their non-serialized counterparts, regardless of the card's actual strength in a game