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Invisibility

Invisibility is not found in the core Epic Duels game from Hasbro, but can be easily incorporated. Certain custom decks grant their character(s) invisibility; just remove invisible characters from play, but be sure to keep track (in your head) of where they move to. When a character is invisible, the following rules apply:

Invisible characters cannot be targeted by Special cards or attack cards.
Invisibility lasts until the invisible character attacks, or plays a special card. An attack made while invisible is undefendable.
Other characters are not considered when invisible characters move. If an invisible character turns visible while in the same space as another character, simply move the (formerly) invisible character to the nearest available empty space. If the invisible character is becoming visible because they are attacking, the attack happens before the move.

Using invisibility is a dangerous ability though. Remember, the highest value attack that a character who is able to turn invisible has equates to direct damage, because the attack is undefendable. On the card that grants invisibility, you should name the circumstances where invisibility ends, and there should always be two ways for invisibility to end, one of which your opponent can enforce. For example, my Nom Anor deck allows any opponent to be able to discard 3 cards to turn Nom visible.