Essence of the Archmagos
*Gain the form of an Archmagos of the Adeptus Mechanicus. You are on the level of intelligence and experience as Belisarius Cawl the creator of the Primaris Space Marines. Due to that you may have a variety of augmentations and cybernetics that a member of the Mechanicus might have access to.
*Have a Forgeworld that is loyal to you in a star system rich in resources for your hungry industry. This Forgeworld can build most common Imperial technologies including a moderate ability to produce spaceships whether it be frigates or lumbering tradeships. It may or may not have records of STC fragments buried in its archives that could make it the second coming of Mars in importance. The Forgeworld is fully manned and built up its forces to fight wherever you desire. It even has reliable cloning technology to rapidly replace losses.
*You have a small fleet of Mechanicus warships including a venerable Ark Mechanicus that is not like the Speranza.
*Optionally you may be dropped into the Warhammer 40k setting anywhere between the peak of the Great Crusade all the way to the dark present.