Creating Lightning Strikes
Inkscape Special FX tutorial
Start with a dark rectangle as the background for the effect.
Draw a shaky line with the freehand tool (F6). Start by adjusting the smoothing (simplifying of the line) to ~30 to keep a the amount of nodes manageable.
Select the Stroke paint and the flat colour option and a light blue colour (e.g. RGB 0/ 225/ 250).
Adjust the stroke width to get a line of medium thick-ness.
Add some more nodes if needed to get an even spread of nodes. Add some shorter lines with a thinner stroke. Select the lines, convert all of them to paths.
Combine the shapes with the Path/ Union option (CTRL + +).
Edit the nodes to create some variation and form sharp ends to the lines.
Duplicate the lightning shape and add a blur effect to one shape (Blur/ Filters/ Fancy Blur) to create the glow. Move this shape below (Page Down) and add a gradient fill (white to white with high alpha) to the top shape.
Details and Glow
With a some additions it turns into a nice lightning strike at night.
As with most effects it’s a matter of playing around with them to get them right. Alter the colours, change the line width and the deformation of the nodes afterwards until you get the effect you are after.
If you want to animate these I suggest doing the lines first and altering a copy of the line shape in a new layer [see the animation tutorial for this]. Animate the shape roughly and not too similar. After creating a few variations of the lightning strike, start with the conversion to paths.
I hope this quick tutorial is helpful to some.