The Shadows of Abaddon mod currently adds six paintings, which with one exception can all be purchased from the Decorationist. Their tooltips generally contain a person's name, apparently intended to credit each painting's artist; some names may be in reference to someone, though some correspond to the painting's designer.
'PUNY MORTALS I CAN EXIST IN AND POSSESS A VARIETY OF OBJECTS TO OBSERVE YOU, EVEN FROM OUTSIDE YOUR DREAMS. I MAY APPEAR TO BE A PAINTING, BUT I AM ALWAYS WATCHING. TREMBLE IN FEAR AND DESPAIR UNDER THE GAZE OF ABADDON THE ETERNAL.'
A portrait depicting Abaddon's six eyes surrounded by a purple haze.