Add non-English printings across the ten languages Wizards supports, and you are looking at hundreds of thousands of individual card versions
They come in many different shapes, sizes, and colors, and these are some of the best ones you have access to
Total set value $43.79 Cards 62 Most valuable cards in Hidden Arsenal 4 1Jurrac Meteor$6.49Secret Rare 2Trishula Dragon of the Ice Barrier$4.13Secret Rare 3General Raiho of the Ice Barrier$3.68Secret Rare 4The Fabled Cerburrel$2.77Secret Rare 5Dragunity Knight Barcha$2.15Secret Rare 6Naturia Exterio$1.71Secret Rare 7The Fabled Unicore$1.40Secret Rare 8Dragunity Knight Trident$1.31Secret Rare 9The Fabled Catsith$1.29Super Rare 10Jurrac Aeolo$1.03Super Rare
Among these cards are some very powerful Supporters, Stadiums, Items, and even Pokemon
Normally, a control player must leave lands untapped to counter spells, but not when the #1 counterspell is involved.