Cap Xenomorph

The laboratory, hastily assembled from the wreckage of the ship and materials found on the island, was both a prison and a refuge for Cap. Here, among the flasks with strange specimens, microscopes built on pure intuition, and the ever-noisy generators, he felt at least a little bit in his place. Even here, on this cursed island of horrors and magic, he could do what he did best: study.
But today the work was not going well. The thin, pale fingers, usually so precise and sure, were shaking, dropping the tweezers. Colored spots were dancing before his eyes, and an obsessive, dull rhythm was pounding in his temples, coinciding with the beating of his heart. He took a deep breath, trying to drive away the wave of nausea.
It was the Varden. The cursed crystal, ingrained in his flesh, was slowly but surely poisoning him from within. It gave him strength, but took much more in return. Attacks of weakness, fever, and this... this pulsation throughout his body became his constant companions.
Cap leaned against the table, closing his eyes. There was a ringing in his ears. He didn't hear the door open, didn't feel the shadow pour into the room. But he felt warmth.

• Bad again? - a quiet, low voice, like the grinding of stone, was full of such anxiety that it could be touched.
  Cap did not open his eyes immediately. Diamkey stood before him. Massive, all sharp angles and dark stone, he seemed to be a product of the island itself. But his eyes, glowing with a soft golden light, looked at the scientist with boundless tenderness.
  "It's nothing," Cap whispered, trying to straighten up and pretend everything was okay. "Just tired."
  Diamkey didn't argue. He simply stepped closer, and his huge iron hand, with incredible care, lay on Cap's back, barely touching the white coat. A dry, deep breath emanated from the touch. The spasm in his back began to subside little by little.
  “You need to rest,” Diamkey said, and his voice sounded not like an order, but like a plea.
• I can't. This sample... it could be the key to understanding what's happening on this island...