Rex falls to his knees from the sudden outburst of the two kingly energies that are rejecting each other and coupled with the Ancient Rune of Harmony that came out of nowhere. None of this is expected, he was desperately trying to collect himself for the sake of revenge.
At this point Rex has already accepted his fate, the world wants him to live a life of hatred.
Maybe that's the only path that is laid out in front of him to keep on living in this world of madness, he slowly started to see the clear picture now. Rather than keeps on rejecting, it's better that he embrace his role in this world.
Clenching the ground with both of his hands, Rex's purple eyes glared at Sebrof and Giana.
Upon looking at Rex that suddenly fell to the ground from the outburst of his own energy, Sebrof grabs the Silver Eye stabbing him before pulling it out. Silver weapons don't affect humans, it hurts but he ignored it and break-free.