That text gets stapled onto quite a few cards now, including Ramunap Excavator, Conduit of Worlds, and Ancient Greenwarden, to name a few
The Secret Rainbow card is even more uncommon, with around a 1/1271 chance of drawing it from a booster pack
The card shows its age in its rules text as it makes use of the outdated term "bury." Cards with the bury mechanic have been errata'd to say instead "put a permanent into its owner's graveyard" or "Sacrifice this permanent." In other words, the true cost of playing the Dreadnought is in having creatures with a total power of 12 or more on your board to sacrifice when it enters the battlefield
Indeed, this deck boasts plenty of those which is also what helps it be one of the more well balanced control decks
That's about $4.60 a pack, and you also get a foil promo featuring Cleffa or Cyclizar
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