In the original, there were 4 Codex pieces, yet for the special there was only one.
Aisha's first appearance.
In the original, the Shadow Phoenix was never referred to as Darkar.
In the original, Darkar made fake Professor Avalon to capture Bloom, but in this version, Darkar disguises himself as Professor Avalon to capture her.
In the original, Bloom did not transform into Dark Bloom until the fourth segment.