Text (IA+errata): X is the number of artifact and/or creature cards in an opponent's graveyard as you cast ~this~. ; Distribute X +1/+1 counters among any number of target creatures. [Oracle 2009/07/08]
A "creature card" is a Creature card or Artifact Creature card. [D'Angelo 1999/05/01] Older cards of type Summon are also Creature cards.
Until Oracle 2008/07/01, this card allowed X to be any amount up to the number of artifact and/or creature cards, but now it must be exactly equal to that count. [D'Angelo 2008/07/12]
