This is the official black magic spoiler for version 1.3 of Martin's Dungeon Bash.
Several types of monster in Martin's Infinite Dungeon have the power to use black magic against the player character. This allows them to blast the character with magical energy (possibly without needing to be on a roguespace cardinal), to teleport around the dungeon level (possibly summoning other monsters at the same time), and to afflict the player with various unpleasant conditions.