stone vs SM

He clawed at the smooth surface of the dark stone, allowing his gladius to tumble from his grip and into the filthy water below. The unsuccessful Scourge followed the weapon and was in turn followed and buried by the falling blocks of the collapsed tower.”
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	 The giant had torn the remainder of the base-block out of the arena floor and was once again hefting the rock above the flat-top of his blond hair. Alighieri prepared himself to dive left or right out of the boulder’s trajectory. At that moment, like a daemon of the deep, Kersh broke the water’s surface. Coming up behind Alighieri he grabbed the Black Templar by both the wrist of his swordarm and his neck. The Castellan struggled in desperation but the Space Marine’s speed and agility were no match for the Scourge’s meaty arm-lock.
Kersh held Alighieri to him, holding the Black Templar in place and outstretched, resting his forehead against the back of the warrior’s skull. The Castellan’s face fell as he watched Montalbán hurl the rock at them both. Kersh felt the Templar’s bones break as the stone shattered against Alighieri’s presented form. The pair were smacked down through the water, leaving a cloud of rock dust to mark the point of dreadful impact.
Once again beneath the surface, the Scourge was slammed into the pool bottom by the weight of the broken block. The back of his head bounced off the stone and something cracked. Heaving the deadweight of the sinking rock off both himself and Alighieri’s motionless body, Kersh kicked off the pool floor only to find his right leg wouldn’t answer. It was broken and useless. Clawing for the surface with one hand he dragged the Templar behind him with the other.
He need not have bothered. The arena was morphing about them once again with a mechanical shuddering. Water drained about the Scourge through the grilles, and the pool bottom rose up to meet him.
All three Space Marines were now back on the same level. Alighieri was a broken and bloodied mess. Half of his chest had been caved in by the rock’s impact. Kersh slithered up beside him and put his ear to the other half and then to the Black Templar’s torn lips. Incredibly, he was still breathing. Barely.

Legion of the Damned pg. 162 and 164