[quote]So what exactly are the Engineers? Are they some kind of bio-technological organism? [/quote] Yes. They were created by the Forerunners as biological supercomputers to maintain their technology, and were even given their own distinguished rate in society - but nobody really liked them because of the smells they produced. They had no political power or even so much as a voice to represent them. [quote]Are the Flood just Precursors and how?[/quote] Don't know what you mean by [i]just[/i] Precursors, considering they're the most powerful beings ever to have existed... The Precursors sought out survival strategies when the Forerunners rose up against them. Some Precursors went into suspended animation and have yet to be accounted for, while others created a regenerative powder which would restore their old forms and was placed on automated ships. Ancient humanity discovered these ships and their cargo, and experimented with it. When used on their pets, the Pheru, it demonstrated psychotropic effects such as increased docility so use of the powder became widespread. However, time had rendered the powder defective (10,000,000 years, to be exact) and eventually the Pheru became sterile and started exuding strange fleshy growths which other Pheru and eventually humans and San'Shyuum felt compelled to [i]eat[/i]. The first stages of the Flood then manifested in its feral form, and because of how widespread use of the powder had become across the Human-San'Shyuum empire whole worlds fell in quick succession and humanity was on the run across the galaxy as they burned whole worlds to eradicate the Flood. [quote]Why is it that by the time of the halo games taking place that the Covenant became more advanced than the humans? Wouldn't the forerunners have favored the humans and left more behind?[/quote] The Covenant's formation was never a planned outcome. The Keyship being left on Janjur Qom for the San'Shyuum was likely part of a plan to reconnect humanity with the San'Shyuum (since only Keyships can open portals, and humanity had the portal to the Ark on Earth which is where they were meant to go to discover the truth about their inheritance of the Mantle), but instead they discovered the Sangheili and everything pretty much went downhill from there. [quote]One more, who was the Original Didact? And was he split (or why?) was he separated into the iso and ur?[/quote] The original Didact, the Ur-Didact ('ur' being the German prefix for 'original'), had to perform a mutation on a Forerunner called Bornstellar in order to give him access to the Domain and advance his maturity. They were pretty much on the run at the time though, the Didact passed on his knowledge, wisdom, and memories to Bornstellar as the Master Builder eventually caught up to them and had the Didact supposedly executed. Bornstellar would then go on to assume the Didact's role and responsibilities. However, the Master Builder did not actually have the Ur-Didact executed. Instead, he shoved him into a stasis pod on a derelict ship with his other political enemies and sent them into a Burn - a star system totally infected by the Flood. From there, the Ur-Didact was captured by the Gravemind and subjected to the Flood's malediction - driven insane by the experience. Instead of killing him, the Gravemind sent the Ur-Didact back to the Forerunners under the guise of a legendary warrior returning in the Forerunners' most dire hour of need as the Flood threat reaches its peak. But the Gravemind really sent him back to cause chaos and dissent in the Forerunner ranks to further cripple their morale when they eventually saw what the Ur-Didact had become. In the years prior to this, Bornstellar, now known as the IsoDidact, served as the military commander of the Forerunners' forces and had developed entirely differently to the Ur-Didact. Where the Ur-Didact vehemently hated the Halos and was against their use, the IsoDidact had come to accept that firing the rings was the only way to defeat the Flood. The Ur-Didact finds an alternate solution through the Composer, transforming his loyal Warrior-Servants into Promethean Knights and then turning on the indexed samples the Librarian had collected of humanity. The Ur-Didact hoped to exploit what he believed to be our species' natural instinct for war, while also imprisoning us as final payment for humanity razing Forerunner worlds during their war with the Flood. The Librarian, as we see in Halo 4's Terminals, stops the Ur-Didact and imprisons him in a Cryptum within Requiem. The purpose of this was to have his mind connect to the Domain which could cleanse him of the Gravemind's malediction, he was meant to awaken fully healed with the purpose of becoming humanity's champion and teacher to help our race attain the Mantle. She left behind the Janus Key on Requiem to help him with this. But her plan went wrong as, while she was trapped on Earth, the Gravemind told her that the Domain is actually a Precursor consciousness and will be wiped out when the Halos are fired - condemning the Ur-Didact to 100,000 years of stewing in his own insanity. The Librarian attempts to warn the IsoDidact not to fire the rings, but she realises it's too late - the Halos have already been fired from the Lesser Ark and their effect had simply not yet reached Earth. Hence why the Ur-Didact is the antagonist in Halo 4, his mind is still tainted by the Gravemind.