The item is called Shadow Essence in Castlevania Puzzle: Encore of the Night and raises one's shadow affinity, although it doesn't help unlock Shadow spells.
|Item Data: Resist Dark|
|Image||Name - Game|
|Type / Users||Attributes / Consume||Statistics / Sell||Found||Notes|
|Resistance to darkness [use]|| Medicine (Attribute Potion)|
| Attrib: Dark|| Find: Black Marble Gallery, Castle Keep, Necromancy Laboratory|
Drop: Karasuman, Phantom Skull
|Gain resistance to dark spells and attacks.|| Enchanted Soul|
| Rarity: ***|
Drop: Arc Demon
|Increases your affinity to Shadow for one battle. Does not unlock spells|| Item (Medicine/Attribute Potion)|
| Attrib: Shadow affinity +10||Sell: 7S 20C|| Drop: Winged Guard, Werewolf, Yorick, Flea Rider|
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