The moon in Isaacs avatar is how we northerners will see it in the depths of winter when it's setting. I think it's purely due to perspective of the rotating earth but it will rise with the claw shaped thing pointing up and set with it pointin down. More noticeable in winter as the axis tilt that gives the longer nights mean we see a full moon for more of the night. The full moon rises when the sun sets, sets when the sun rises, and if the earth were transparent and we could always see the sun, the full moon is always roughly opposite the sun. That's why a winter full moon goes high in the sky, because the sun dips far below the horizon, and a summer full moon only comes low in the sky, because a summer night only sees the sun dip below the horizon a small amount. So whatever the sun does, a full moon mimics it opposite.