reserve and duplicates

[BasiliskFang]

what if the 8f would stay in your hand (not discarded) but if they do attack dazzler and you do defend with the placed 8, the 8 in your hand becomes unusable.

[gameplan.exe]

what if the 8f would stay in your hand (not discarded) but if they do attack dazzler and you do defend with the placed 8, the 8 in your hand becomes unusable.

yeah, the Dazzler situation is definitely trickier to sort out.

This is directly from the Rule book:

The exception to this rule is the cards Placed to the Reserve Character. Cards Placed to the Reserve Character are not considered part of your Hand for purposes of discarding unless the Reserve Character has the ability to play those Placed cards during the battle (e.g., their Inherent Ability or the Special card allows them to play it from Reserve). Therefore, if the Reserve Character has the ability to play the card Placed to them during a battle, duplicates that are drawn in subsequent hands must still be discarded.

The biggest difference between this, and the rule about discarding unusable cards that you can make usable, is that your own ability to "make them usable" is not a consideration when it comes to duplicates. So, if you have "Tapping the Speed Force" for TheFlash (JA-Special, using E PC), but you have no E PC this hand, the card would be unusable and would need to either be placed or discarded. However, if you also had Storm's "Gathering Winds" (OE-Special, retrieving E icon Power cards) and you know your top Power card in your Power Pack is E, then you don't have to discard the JA. However again, if your ability to make the JA playable somehow depended on your opponent (let's say a made up card that allowed you to avoid an attack then retrieve an E PC), you cannot make the JA playable of your own volition, and it is therefore deemed unusable.

But all of this is relevant to the usability of a card, and whether or not it must be discarded - not relevant to the duplicity of a card. The rules never say anything about how the Reserve character can make the card usable, only that they can 

[BasiliskFang]

this is weird...