Creature - Spirit 1/1, BB (2) Haste At the beginning of your upkeep, if Nether Shadow is in your graveyard with three or more creature cards above it, you may put Nether Shadow into play.1
Illus. Christopher Rush
Note that bringing the Shadow back into play from the graveyard is not a spell, it is an ability. It cannot be countered with something that counters spells. [bethmo 1994/05/14]
Since it comes into play due to triggering at the beginning of upkeep, it is not possible to get an infinite loop with four Nether Shadows. [D'Angelo 2000/03/03]
Note - In all printings it was of creature type "Shadow" but it is now of creature type "Spirit".