Another answer to a technique question from Reddit: Here's a fast way to make a bunch of mountains fading into clouds in Illustrator. There are others; this is the way I'd do it.
1. Make two swatches: pink, blue. Check the “global” box in the swatch options for each of them. Draw a big pink rectangle on one layer, make a new one to draw mountains on.
2. Draw a vague inverted-u shape with whatever tool is quickest. I like the pencil tool, double-click on the pencil tool; turn on 'fill new pencil strokes' and 'edit selected', turn off 'keep selected', it's defaults are terrible for fast drawing.
3. Open the Appearance palette. Visit its menu, uncheck “new art has basic appearance”.
4. Fill your shape with a pink-blue gradient made from those two global swatches. Set it to 90°.
5. Add the roughen and tweak effects to this fill. Roughen at 0% size, detail to taste, corner points; tweak 0% horizontal, vertical to taste, play with the modify checkboxes.
6. Add a new fill using the button at the bottom of the appearance palette. Make it solid pink and on top of the first fill. This will be the clouds.
7. Add the ellipse effect to this fill. Relative, 0pt of extra width/height.
8. More effects: transform, 50% vertical, centered on the bottom center of the object; roughen, 4%. 5/in, smooth; Gaussian blur, 13px.
9. Graphic Styles palette: make a new style.
10. Using this style, draw more mountainous shapes. Use object>arrange to put the lower ones nearer, if you didn't draw them in that order.
Stuff in the Appearance palette should be arranged like this.
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