Enclosed geometry: rectangle, ellipse, polygon, freehand and the revision cloud variants.
Shape tools draw an enclosed outline with an independent stroke and fill. Every shape can be filled or left hollow, and the outline colour and the fill colour are separate channels on the same markup.
Four of them are revision clouds, which scallop the outline. A cloud is its own tool rather than a setting on a plain shape: pick Cloud Rectangle to draw a clouded box, not Rectangle and then a switch.