Teres

Oh, absolutely not. This is just one of those books/series where deprivation or injuries kill or don't kill you based on nothing but authorial fiat. In this book alone we have a character instantly die from a small stab wound to the gut. He doesn't even bleed out. The moment the knife gets him in the "lower abdomen" he drops like he just got shot through the head. Not so much as any death throes.

Whereas later on Axis gets torn apart so badly his LUNGS ARE EXPOSED he... doesn't die. In fact he somehow stays alive for at least fifteen minutes before getting healed with magic.

Because, you see, the author did not need the first guy to stay alive but needed Axis to stick around, so therefore the one is insanely easy to kill while the latter is functionally invincible.

And as it's never at any point stated that the Avar don't need as much water as humans (indeed, they pretty much ARE humans physically), if the author had used "well the Avar are just different" as an after the fact excuse we'd all know she was full of shit.