Quicksilver can be found in Kasumigaseki. Flynn will need the Demolingual App in order to communicate with her. Quicksilver can teach Flynn the Mazio skill through her Demon Whisper. Alternatively, Quicksilver will evolve from Poltergeist once it reaches level 17. Quicksilver can also potentially give Flynn the "Isis' Search for the Coffin" Challenge Quest if spoken to.
"Female poltergeists that like to pull pranks. They break furniture and throw things around, as well as write the letter Q on windows and mirrors with soap or lipstick. They are easily bored, not staying in the same place for very long. In general, they are not dangerous spirits."
—Shin Megami Tensei IV Apocalypse compendium
Quicksilver appears in Kasumigaseki or can be obtained by letting Poltergeist evolve at level 23. Quicksilver can teach the Mazio and Shock skills through her demon whisper and benefits from learning Electricity and ailment skills.
Quicksilver is also capable of evolving into Raiju upon reaching level 30.
"Female poltergeists that like to pull pranks. They break furniture and throw things around, as well as write the letter Q on windows and mirrors with soap or lipstick. They are easily bored, not staying in the same place for very long. In general, they are not dangerous existences."
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