It was a three ability, three mana, solid body that was a lot in one package
While Darkness is just a colorshifted Fog, it has become a very scarce card due to limited availability and it was actually the most expensive card reprinted in any of these precons

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The question on everybody's lips has been is Cloud good enough to replace the many already terifying mono-white Equipment commanders like Sram and Balan
It's a subtle way to generate advantage, saving you from being 2-for-1d and shining in Limited and formats with small card pools
I fully acknowledge that the Commander community has grown such that there are huge amounts of people who enjoy facets of the format that might not be my cup of tea