Creature — Illusion Sliver 1/1, 1U (2)
Common
All Slivers have "{1}: This permanent becomes the creature type of your choice in addition to its other types until end of turn."
Taking the form of a junior researcher, the first sliver slipped out of Riptide.
Illus. Ben Thompson

10/4/2004: Unlike most type changing effects, this one adds a creature type instead of replacing existing creature types.
Legal in Vintage (Type 1)
Legal in Legacy (Type 1.5)
Legal in Classic (MTGO)
Legal in Commander