Encards are what Enterrans become when defeated. The cards can be absorbed or eaten by other Enterrans to gain some of the defeated enterran's powers. If the card is left intact, they can come back to life, if the card is destroyed, the Enterran is gone forever.
It is not uncommon for Enterrans to take each other out for their cards. By absorbing these cards an Enterran will absorb all the powers and some of the appearance of the fallen one. Their is no apparent upper limit to how many cards can be absorbed. Gyasa was able to absorb dozens of reptile cards at once while Caris absorbed a single encard made of combined multiple ones and became a hideous monster.