Hollow Mana

{5}: Put Hollow Mana into your graveyard from exile. Activate this ability only if Hollow Mana is exiled.
{8}: Counter target spell. Exile Hollow Mana from your graveyard. Activate this ability only if Hollow Mana is in your graveyard.
The last resort of any mage during a long trip or dark night is to protect themselves with old memories.