What would the pattern look like?

If you wanted to make this shape in cast metal, what do you think the pattern would look like? If you were to cast the piece standing (as shown) it would have to include draft, making the wall thickness too inconsistent. The most effective way to cast the piece would be using a core.

Follow up:

The picture below shows the pattern and corebox used to make the casting. Being a simple shape, the pattern isn't very difficult to create, however there is a lot more work involved than some may realize.

This isn't the only way to make a suitable pattern for this casting, but in doing the pattern this way, it allows for multiple castings to made from the pattern.