I've read something saying that First Impact was what wiped out the Dinosaurs. Since by "Impact" they seem to mean a great catastophic event that involved unimanginable loss of life.
Odd thing that doesn't make any sense, though: If LCL is the "primordial soup" that all lifeforms on this planet are based off of, would First Impact have to be the meteorite strike that seperated 1/4 of the Earth, which later formed the moon? If you remember in the show, they mention First Impact IS the meteorite strike that seperated the mass which formed the moon from the Earth.
Also, if you think about the Egg of Lillith for a second, it was made of an incredibly strong mineral, which was rare for the Earth. So, at one point in time, Lillith had to "crash land" on the Earth, and that's what supposedly started life. Unlike an exact religious context, I'm betting Adam was formed of Lillith, because she was bored. The other Angels were probably formed the same way.
As for how the 18th Angel (mankind) was formed, I have a slightly different view from the norm. Quite a few people believe mankind was formed by all the little components of the Angel Humanis splitting apart, taking their own AT Fields, and doing whatever the hell they want. However, that seperation caused that feeling of emptiness in all of us.
Instead, here's my theory: if Lillth is responsible for all life on the Earth, including plants, bacteria, etc, then all the LCL that makes up all lifeforms on Earth has to be subdivided due to the complexity of the lifeforms in question. For example, humans are far more complex than insects, requiring far more LCL to make our physical forms. Therefore, there are far less of us compared to the number of insects on the Earth. Same thing applies to the Angels. Notice how only one attacks at a time, and from Episode 10, we see an Angel hatching?
Perhaps the 3 billion human lives lost due to Second Impact (and all the civil wars afterwards) were a necessary sacrifice to transfer all that LCL for use to form the Angels. Remember how it became far more difficult for parents to have children after Second Impact? Misato mentioned something about the Room of Gauf, where all the souls for newborn children were harvested for their intended purpose. Perhaps the reason the Room of Gauf was being "scavenged" as she put it, was due to the fact most of the souls of the dead were now making up the Angels.
Basically, by initiating Second Impact, Seele didn't prevent Adam AND the Angels attacking at once. Instead, they traded a future assault from Adam for 15 engagements with Angels of varying offensive and defensive strengths.
So what does this mean for mankind's ultimate form, according to Seele? In reality, this "ultimate form" is just the intial phase of life's formation on the Earth. They didn't achieve any ultimate form at all, but just started the loop again, to reach the same conclusion of mankind's evolutionary dead end some billions of years later (if mankind doesn't escape from their dream world, and their will to live forces their ego-barriers to assemble the LCL back into homo-sapien sapiens. In conclusion, the 18th Angel Humanis never existed as Seele thought it did. Instead, like the Angel that invaded the Magi, we exist as a collective of individuals, all with our own little part to play in the course of history.
Of course, I'm approaching this from an evolutionary perspective, and not a religious one (can't stand frosted flakes, or any form of their ideology).
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. They also show images of Ritsuko and Misato's clothes in LCL implying what happened.
