As it is now, they are just too slow to really be of value to most decks, and youre probably better off playing the depletion lands, like Saprazzan Skerry, instead
Other cards have activated abilities that require energy to activate
By shining a light through a card, you can test its authenticity, this is known as the light test
Having only been printed originally in Portal Three Kingdoms and then as a Judge promo, the card was extremely expensive until the Double Masters printing
Other Spells : Seize the Soul, Elixir of Immortality, Undying Evil, Obelisk of Esper, Sacred Mesa, Syphon Flesh Some spells that can create fodder for sacrifice will certainly help keep Ertai frisky
The Great Sleep Necron Dynasties is good deck to buy if you're starting out in the format or if you're a more enfranchised player looking to have a precon to keep together