The grunt grabbed his neck, and Kendul gasped for air, and felt a feeling not unfamiliar to a Sand Master, in fact, it was a feeling he felt a few seconds prior, when he controlled the Ribbons. He was dehydrated. Although to a normal, weaker person that would be normal, for Kendul, it could be his doom.
As the man somehow drained the water from his body, he frantically looked for a way out. He knew he needed to focus, to calm down. I will not be killed by some faceless, worthless, dime a dozen scum! He concentrated on the enemy, and for a second, it felt like time stopped. Kendul looked at the mask, completely shielded, no way to get even the tiniest bit of sand in. Wait, if even a single grain of sand can't get through, how does he breath? He struggled to tilt his head to the side, but he managed it. There was a a lump in the back of the armor, big enough for a small tank. Wait, he can't be exclusively using air from it, it's barely large enough for an hour, so then how... That's it! It must have holes in the back to feed in oxygen from the surrounding area, with the tank acting as a backup! There was only one problem: He didn't have enough safe water. Most of it was drained, if he used any of it for sand mastery, he would die. But, there was another way, dangerous. Even if he lived, he would be weakened, and likely wouldn't be able to fight. I don't have any other option.
And so, he accessed the water in his own blood, and directed all the sand he could into the holes in the tank, filling it, and the mask, with as much sand he could.