cr:1.8.4b

A conditional effect, written in the format “[EFFECT] unless [OPPCONDITION],” is an effect that is conditional on the opposite of the OPPCONDITION. This effect’s condition is only met when the OPPCONDITION is not met, or the OPPCONDITION is an effect that fails.[1.8.9] If the OPPCONDITION is an effect instead of a condition, it is an optional effect.

Example: Pitfall Trap has the text “. . . deal 2 damage to the attacking hero unless they pay {r},” which is a conditional discrete effect, that is conditional on the attacking hero not paying the asset-cost.

Note: An effect that reads “Deal 2 damage to the attacking hero unless they pay {r}.” can be read as “The attacking hero may pay {r}. If they don’t, deal 2 damage to them.”