Well of course, Dihydrogen-Oxide kills hundreds of thousands of people every year - even small amounts can be fatal.

Statistically 100% of everyone who ingests dihydrogen-monoxide or has it present in their body dies.

Even more alarming - 100% of everyone who doesn't ingest or have enough dihydrogen-monoxide in their body will also die.

Fatal with, fatal without - it's the ultimate killer.