Smoke & Explosions
By Rio

In continuation of the fire effects tutorial, let's take a look on how to draw smoke and explosions.
Smoke Step-by-Step
Smoke, when no wind is present moves steadily upward in a column, usually widening as it grows further from the flame. Above, you can see the progression of drawing smoke. Starting off with a basic cone shape, you just built and stack semi-circles with varying sizes and you've got yourself a simplified version of smoke.
If you would like to make a more realistic smoke stack, just as you would detail a tree, just add multiple short lines and straight lines to add the wispy look of smoke. To the right of the example are some close-ups.

When there is a gush of wind, smoke will become engulfed and curl up in itself to form a sort of mushroom-like effect.

This can also be used to display a tremendous explosion but make sure to straighten out the "wind" lines and push the smoke up to become flatter.

Moving on, to create explosions, all you need to do is add two important elements. 1) Outward force and 2) billowing smoke effect as shown below:

For the outward force, it is usually depicted in a slim columnar form with a lot of short multiple lines but can also be drawn with straightened lines for those extra powerful explosion.