The Fourth Painting was an altered representation of a fragmented genetic memory.
We recovered the third piece from Lieutenant Cavallero's villa and Da Vinci's set is almost complete!
The fourth piece was given to an Inquisition treasurer, Cristoval de Merlo, who is safekeeping it deep underground below the slums of Madrid. We must be stealthy and will need to disarm traps in order to recover it.
The Spanish Assassins successfully retrieved the fourth painting from da Vinci's The Celestial Mysteries set.