This trick is essentially the same as the Pass under shower pattern except with the added excitement of an orbit made before a Slam throw.
Start with two balls & hold one in each hand. Hold one hand at the centreline of your body & at waist height. Hang your other arm down by your side then bend your elbow so that the ball is held level with your shoulder.
Now Chop the hand at shoulder height diagonally down across your body to a point level with the opposite elbow. Then start to circle back & carry the ball down & back underneath the way it came. Just before you carry back over the other arm throw the other ball straight up as an Under the arm throw, continue the carry underneath the ball in the air. Finally as the thrown ball peaks swing the carrying arm down over the top of it & throw the carried ball as a Slam into the opposite hand. In the same movement Claw the first throw & then hold it at waist height at the centre of your body.
Try not to make the vertical throw too high, otherwise you'll have to reach up to make the slam which will be tricky to keep under control. Practise this leading from both hands.
Take all three balls & juggle a cascade. Pick a ball & as it comes round catch the ball at its peak then chop it down across your body just as before. Make the next throw straight up under the chopping arm, after making the throw catch the third ball with the same hand. Orbit around the ball thrown under the arm then at the same time as you throw the slam, empty your other hand by making an Over the top throw. Catch the slammed ball then resume the cascade. Again practise this move on both sides.
Again with three balls do exactly the same again but as soon as you catch the slammed ball, lift it up & chop across your body to lead into the orbit move on the other side. Do the same again with the second slammed ball & so on.
In this pattern each ball stays in its place so if you are juggling with three different coloured balls the slam, under the arm & over the top throws will all be made with the same ball each time. Focus your attention on the ball that you throw straight up under the arm each time, try & keep the orbiting carry tight to this ball.