Granted. You discover it because, somehow, your house gets flooded in it.
Hm…, just silently suffocating won’t cut it, will it? So, yeah, you can detect it in time because it smells really … ignoble. Oh, and you can’t get rid of the stench for years 
I wish I could wield a sword made of technetium, no matter how briefly, and live to tell the tale.
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The red lake has been forgotten. A dust devil stuns you long enough to shroud forever those last shards of wisdom. The breeze rocking this forlorn wasteland whispers in your ears, “Não resta mais que uma sombra”.