Players will need Inquisitor - Martyr in order to play Inquisitor - Prophecy.

New Class: Play as a Tech-Adept Inquisitor. Summon and enhance units to help defeat enemies and complete investigations. This new summoner class comes with new unique abilities and mechanics, a unique skill-tree and various new melee and ranged builds.
New Campaign: The story of Inquisitor - Martyr continues in three new chapters, with one chapter solely focusing on the Tech-Adept, as its story slowly ties into the main plot.
New Environments: Players can discover huge monasteries, hazardous factories, unforgiving deserts and ruthless worlds engulfed by lava and volcanoes.
New Enemy Races: Inquisitor - Prophecy adds the Eldar and the Tyranids as new enemy races.
New Gameplay Mechanics: Inquisitor - Prophecy is based on Inquisitor - Martyr's 2.0 update, bringing the base game's new level cap, redesigned loot-system and leveling, its new end-game, the co-op campaign mode, new items and a much faster, ARPG-focused gameplay to the new expansion as well.

Warhammer 40,000: Inquisitor - Martyr - Prophecy