Master slide?

Hello and welcome to Apple Support Communities, acbrennan013,

For information on master slides, follow the steps in this article to create one:

Add and edit master slides in Keynote on Mac - Apple Support

"You can make the same kinds of changes to a master slide that you make to a regular slide—for example, modify the appearance of text, change the slide background, and change the size of the images. The changes appear on every slide in the presentation that’s based on that master.

1. "Click  in the toolbar, then choose Edit Master Slides.
2. Do any of the following:
3. 

• Click  in the toolbar, then click to select a master slide.
• In the slide navigator, click to select a slide with a layout similar to the layout you want, then press Return.

1. Double-click the name of the master slide in the slide navigator and type a new name.
2. Modify the slide however you like by adding text, images, shapes, placeholders, or other objects.
3. See “Add text and media placeholders,” below.
4. When you’re done editing, click Done at the bottom of the slide canvas, or click  in the toolbar, then choose Exit Master Slides."

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