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Use the Eraser tool

If you use the Eraser tool in Layer Source & Paint or Paint Only mode, it creates Eraser strokes that can be modified and animated. In contrast, using the Eraser tool in Last Stroke Only mode only affects the last paint stroke drawn and does not create an Eraser stroke.

To temporarily use the Eraser tool in Last Stroke Only mode, Ctrl+Shift-drag (Windows) or Command+Shift-drag (Mac OS).
  1. Select the Eraser tool from the Tools panel.
  2. Choose settings in the Paint panel.
  3. Select a brush in the Brushes panel, and set brush options.
  4. Drag through the area you want to erase in the Layer panel.

    Each time you release the mouse button, you stop drawing a stroke. When you drag again, you create a new stroke. Shift-drag to resume drawing the previous stroke.

Note: If you use a pen tablet, pressing the eraser side of the pen to the tablet temporarily activates the Eraser tool.