A digital triptych of the 3 main types of Necromancy from the Locked Tomb series. 

The leftmost side depicts Bone Magic with a darker grey background and a skeleton laid out in a fetal position. From below, an ashy brown hand with dark nails is reaching out to it. 
The center side depicts Flesh Magic. The background is a saturated red fading into a near magenta. Laid in the same position as the skeleton is a fleshen figure, with muscles stretched across its limbs and ligaments coating the rest. Two hands surround it - one pulling up liquid that looks like blood, and another a yellow liquid that looks like fat. 
The right side depicts Spirit Magic. The background is an electric blue. The figure, which is in the same pose as the last two, is featureless and blue-white. In the center of its chest is a hole. Its eyes are wide open, looking at the viewer in shock or anger. There is A hand just above the nape of its neck, which is drawing spiritual stringers from the ghost, as though puppetting it. ALT

The 3 Main Schools of Necromancy.