In the last moment, Chronus decided to throw Ryan at the sun, even if he had to burn as well. He could always recover once Ryan loses his consciousness. Ryan knew exactly what Chronus was thinking, so he fired the arrows to kill him first.
Chronus tried to protect himself with his remaining arm, but in the end, he could only do so much against an enemy that could use the same magic as him. His face and body began to burn even more thanks to the power of the Solar Arrows. Without any other choice, Chronus used Temporal Healing and made his and Ryan's wounds disappear. The mental strain disappeared completely, but Ryan still was suffering more than him.