The Amethyst Guardian

The Sky-flyer came into view over the rise, bristling with armaments. Weapons had been outlawed after the last war on Earth but Elyse had seen pictures of the wounded. Its nose lowered and multiple streams of grey photons spurted on either side of her. She had only two choices, stay and be destroyed along with her research, or jump from the side of Far Mountain to save her work. It was really no choice at all.
The New World sought to abolish the mistakes of Earth's last war. But the colonists had no idea that the turquoise planet they had chosen had once been a battlefield of winged guardians against alien Saurians. The remaining guardians have downed their weapons and are now peacefully settled in the shadow of Far Mountain while the Saurians mass, deep underground. The first wave has begun. The population has been weakened by a parasitic infection and defenceless against the coming assault.
Only Elyse has been able to fight off the parasites invading her body by using her skills as a botanist and the knowledge of the ancient ones. Now she must climb Far Mountain in search of the cure. She becomes the target of a Saurian hit squad. Adrian is a Dark Guardian. He hunts from the shadows, destined to be alone, the ooze of the aliens a stain on his soul. Elyse is like a shot of colour in his grey world.
His duty to protect the shy scientist's her work becomes an obsession. But will he be in time to save her when the Saurians reach her on the Mountain?