A mistake
Underneath the Blade castle, both Vorden and Raten were sitting inside one of the cells. At the moment, the two Blade siblings were busy consuming crystals, one by one, impatiently waiting for the energy to be consumed by their bodies that would hopefully allow them to evolve to the next tier.
Both of them were sitting on the ground, and had a small mountain of crystals next to them. According to Muddy and Tails, the easiest way for their bodies to absorb the energy inside those crystals was just to eat them. However, the downside was the drowsy feeling they would experience as their body was using that energy to grow.
This was why they had decided to do it underground, away from any distraction of beasts or others and even if someone did come down, they would have to go through the cell doors first. To do that, they would have to pass Borden, who acted as a bodyguard for the two of them.