I smell cheeze.

[Boromir88]

Then why doesn't he just say...

Do you not know Death when you see it? Die now and curse in vain!'

Instead of cutting the sentence in half with a cheezy Legolas liner "Die now." I don't see Tolkien as the cheeziness here because he just didn't end it with "Die Now!" Just doesn't sound right, reminds me of "Sleep (hand wave)." Which was just downright bad.

Edit: I'm sure if I look hard enough I can find corny lines Tolkien has too, in fact I know one.
"Shortcuts make for delays, but inns make for longer ones."
This I find really corny, but that good corny, sort of like your Grandpa's jokes, with that quirky sort of humor. Where "Die Now!," or "A Diversion!," or "I see you!" are just...bad.