From the introduction: CONVERTING MONSTERS When I was asked to help write the Menace Manual for the d20 MODERN Roleplaying Game, I was overjoyed to see so many monsters on the list from the Dark•Matter Campaign Setting for the ALTERNITY Roleplaying Game. After all, I’d had a great time writing Xenoforms: Aliens, Demons, & Aberrations with Rich Redman, and I was really looking forward to converting some of those creatures to the d20 MODERN rules.