The Fire Giant from the Blood Rage board game is an excellent mini for testing lava on the base, a fiery sword, glowing runes on the body and OSL effects. My intention was to trial various different effects on different parts of the mini, so just take your pick of the bits you like. This tutorial (including painting the whole mini) was first published in full about a year ago in three separate posts on https://boardgamegeek.com/blog/8627/griff-glowens-beginners-painting-blog

1. Base with Vallejo White Stone Ground Texture. Make sure any other fire areas are primed white. Other areas should be primed black.

Lava and Runes

1. Red Leather to the rims of the lava. I actually used an old pot of GW Bestial Brown but any reddy brown would work. Overlap both the white lava and the black rock.
2. Khorne Red over most of the Red Leather, leaving just some on the rocky edges. I also used a glaze of this (by heavily diluting with Vallejo Glaze Medium) and added to the close parts of the mini to begin the OSL effects
3. Also use the Khorne Red to surround any runes. This will be a base for the next step.
4. Mix Bright Orange & Flat Yellow and dilute with glaze medium. Add the glaze to the lava, especially the line between red and yellow. Keep adding glazes until there is no hard line between the colours. The same glaze can be used for the fiery glyphs in the model, cover both the white and the surrounding red and also on the OSL effects on the mini itself.
5. Add gloss varnish (the rest of the mini has matt varnish)

Fiery Sword

1. For the fiery sword I based the whole sword Flat Yellow then created a mix colour with with Flat Red and wet blended all three colours. Don't do too large an area at once as it must be blended quickly. The idea is for the centre to be bright yellow, moving gradually to red at the outer tips
2. Finish the fire with Smokey Ink on the tips (diluting the ink with matt medium or glaze medium). The very inner runes need to be especially bright so mix Flat Yellow with White and add thin layers to draw the runes
3. Add gloss varnish

Eyes & Mouth

1. I started with the same techniques as with the glyphs above.
2. I then blended thinned layers of Khorne Red , Flat Red , Bright Orange , Flat Yellow and White . I wanted the fire to look dark so added some Army Painter Dark Tone and some Smokey Ink
3. Add gloss varnish

And the model is complete

Front

Back

Side

For a more recent attempt at Lava effects using Arcadia Quest Ignos check out the blog linked above