PowerPoint has two kinds of shadows - shape and text. Shape shadows may be set by right-clicking on a shape (including a text box), choosing Format Text, then selecting Shadow or using VBA via the Shadow property on each shape:
For Each Slide In ActivePresentation.Slides
For Each Shape In Slide.Shapes
Shape.Shadow.Size = 100
''# etc
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How do I set text shadow's properties using VBA? In the UI, these may be accessed by right-clicking on text, choosing Format Text Effect, then selecting Shadow. I've done a bit of digging online and have been unable to find where these properties may be accessed via PowerPoint's VBA API.