Creature - Elemental Serpent 2/1, XR (1) Trample, haste Lightning Serpent comes into play with X +1/+0 counters on it. At end of turn, sacrifice Lightning Serpent.
Illus. John Avon
7/15/2006: If Lightning Serpent comes into play without X being paid because an effect puts it into play or an effect lets you play it without paying its mana cost, then X is 0.