The requirements for the Shadow Form were the same as for other evolutionary branches, only the Attribute Crystal Stone needed to be of the Dark type.
He had already absorbed the Dark Attribute Crystal Stone, but the Insect Continent wasn't short on Soul Beasts with this attribute.
In fact, according to the panel's description, there was no requirement for the Crystal Stone and the essence of flesh and blood to come from the same Soul Beast.
It wasn't out of the question to find a Soul Beast Crystal Stone of another attribute.
However, Han Ning considered that the heart's previous owner was a Dark Attribute Soul Beast. There might still be some Dark Attribute Spiritual Energy left in its bloodline, so it would be best to find a matching Dark Type Crystal Stone. Using a different attribute just felt... off.
'Essence of flesh and blood... isn't a heart the very essence of flesh and blood? Perfect. I still have that giant Winged Demon Heart I haven't used yet.'
