-
If the teleportation effect is a type of technology, possibly it would only work on electrically conductive objects, or on specially primed or pre-treated “projectiles”. Perhaps it could be blocked by certain electromagnetic effects.
-
If it is psionic, perhaps it could only work on objects to which the villain has an emotional or psychic connection for some reason, like playing cards or gummy bears. Even more limiting, perhaps the character is psychically connected to a single object, and after teleporting the Blade of McGuffin into someone, it must be physically retrieved for re-use. Perhaps the villain’s irrational fear of insects or aversion to the color fuschia makes it impossible to psionically concentrate on any target protected by such things.
-
Perhaps the teleportation effect is magical, requiring the villain to employ a ritual phrase or gesture. Anyone who is aware of the villain’s ability would then be on the alert for that ritual action, and would leap out of range or strike immediately to negate the teleportation attack. Perhaps the magic only functions under moonlight or from shadows. Perhaps it only works when the villain makes a sacrifice, such as cutting one’s own hand.
Is this the same offensive teleporter from your previous thread: What would be the best equipment for a lethal teleporter?