• This effect keyword first appeared in the Call of the Crystals set.
  
• poisoned is a keyword negative effect (written in bold in the effect area of the card).

• A hero or ally that is poisoned takes 1 poison damage at the start of each of its controller's turns.
  
• A poisoned hero or ally can still defend, attack, or use abilities (unless some other effect is preventing that).
  
• A target that is poisoned will remain poisoned continuously until it dies or its controller plays an ability that removes the negative effect.
  
• Heroes or allies that are poisoned are shown with an green colored fiery overlay.
  

• If a target can be poisoned multiple times, an ally that is poisoned X times will receive 1 poison damage at the start of its controller's turn.

Some statistics:

• The Neutral faction is the most active in applying the poisoned negative effect, with 4 cards capable of inflicting it, followed by the Shadow faction with 2 cards.
• The Hunter and Rogue classes are the most proficient in using poison tactics, each with 5 cards that can apply the poisoned negative effect.

• Damage reduction from combat does not prevent the poison damage from poisoned, as it is considered ability damage.

Cleric's Mantle, Healing Touch, Jericho Spellbane, and Regeneration, are some of the cards in the Shadow Era game that remove the negative effect poisoned.

The cards that poisoned others are