Why is it so easy to denote the tense mood of Pope Leo X with Cardinals?

None of the figures are looking at each other. The choice of colors and the darkened background suggest an uneasy mood. In art appreciation, Mood is a comprehensive environment, or status of consciousness and senses, that a work of art produces. For instance, the mood of a landscape could be painful or peaceful, deep or dynamic. Color is one of the most efficient techniques to generate a mood in a painting.