Lava base with Mordant Earth technical paint

Red basecoat.
If the miniature is already mounted, paint Heavy Red.
Otherwise, spray paint Mephiston Red.

Red gradient: Gory Red, then Bloody Red.
Draw thick lines (I used a Citadel Medium Wash Brush here), then highlight them with the second color. Don't worry about transitions.

Orange gradient: Hot Orange, then Orange Fire.
Switch to a smaller brush (no. 2 here). I did some highlights of the red lines, but also random lines akin to tree branches to fill the spaces in between. Transitions don't matter, variety is the key.

Finally, yellow gradient: Sun Yellow, then Fluo Yellow. Same idea.

Finally, do the black rim of the base. Then cover the base in gloss varnish. One thick layer is perfect, the shine and protection both matter. Don't skip this!
I read somewhere that 24 hours are required to fully 110% cure the varnish, even if it dries in 15 minutes. I did not do a comparison of waiting vs not waiting - I waited, just in case.

The last step is a thick layer of Mordant Earth. I also apply this to the sole area of the foot, any cloth that may touch the ground while walking, etc.

Finished!