The Star Seal was the second step in the evolution after Phantom destroyed the First Wall. This event was the second one after the First Wall, not at the K2 level.
The point is that the First Wall itself was supposed to be the first cell for the Star Seal, after which the Star Seal would appear, sensing the presence of the star.
Yet, in Adam's case, it was different. His The First Wall didn't need extra time, genes, and energy to evolve into something else, it was too strong for the additional steps.
Tremble. Tremble. Tremble.
With an active shudder, the first star appeared next to Adam - black with burning purple flames billowing around it.
The Evolution Tree proclaimed:
[The first one - the Wall Star.]
Before Adam could say anything, a bright white light illuminated the left side of Adam's face. The bright star floated amidst the darkness, emitting a pleasant, familiar warmth to Adam.