There are so many cards packed into the possibilities, you could fill an entire eight-person draft and not see the same card twice
Much of the meta is centred around beating these decks, and if the list your running isnt prepared for them, you wont stand a chance unless you draw very well and they draw abysmally
These were randomly inserted into standard 151 booster packs (replacing the reverse holo slot) but feature the HD Cosmos foil pattern: Grass, Fire, Water, Lightning, Psychic, Fighting, Darkness, Metal
You can only activate 1 "Terrors of the Overroot" per turn
I'm not sure there is any possible Secret Lair drop in all of Magic that would generate as much revenue for Wizards , and this doesn't even include the number of Masters sets Wizards could sell with cards like Underground Sea in the dual-land slot