Emperor (Warhammer 40,000)
The Emperor of Mankind is the the immortal founder of the Imperium of Man and the most powerful Human psionic known to exist. He is worshipped as a god on all Imperial worlds.
History
The Emperor of Mankind was born in 8,000 BCE, when a large group of psionic shamans gathered in what is now Turkey and engaged in a specialized ritual, the result of which was a male child who would eventually become the Emperor. For millenia afterwards, he wandered the Earth in secret as humanity began to expand into the galaxy.
After the Fall of the Eldar civilization, Human civilization was disrupted by the birth of Slaanesh, which caused intense warpstorms that made travel through the Warp virtually impossible. After these storms subsided, the Emperor, based on Earth, began to unite mankind under his banner. Among his creations were twelve children derived from his own DNA who would become the twenty Primarchs of the Imperial Space Marines.
Current Condition
Following the rebellion of Primarch Horus, the Emperor was forced to enter the Golden Throne, a special life-support system of his own design. His condition continues to deteriorate, however, and while still able to use his psionic powers to maintain the Astronomicon and enhance ordinary human psykers to be capable of astro-telepathy (telepathy over interstellar distances), he is only marginally conscious, at best, and the High Lords of Terra do all decision-making for the Imperium.
There are rumors that this life-support machine is also his bodyguard, and that it can transform into something with 10 times the power of one of the mighty Imperator Titans.