Are you sure you didn't buy the wrong product?

https://liquiddeath.com/products/sparkling-water

That explains it. Chances are I saw the black cans but bought a white one thinking they are all the same.

They sell a carbonated version, and a few flavored versions.

I still buy the carbonated (black can) from time to time. I didn't buy it sooner because I was under the assumption that "Liquid Death" would also be caffeinated, and I couldn't imagine an unflavored caffeinated beverage tasting good.

Caffeine by itself does not taste good so you’d be right. I don’t know how to describe it other than metallicy and funky, neither of which are very helpful. But it doesn’t taste much like anything else I can think of.

Isn't caffeine one of the most bitter-tasting substance out there? Like, it's used to measure bitterness.

Not reading the can doesn't mean you were scammed.

Yeah I originally thought it was carbonated as well when I first saw it (which I drink a lot of). Never had the misfortune of buying one though.

The white can is the only flat water; the black can and the flavored ones are sparkling.

(I tend to drink more Waterloo or Spindrift when not at a bar, personally, but I've enjoyed the flavored Liquid Death that I've had.)

They do sell sparkling products, including IMO the best-tasting flavored sparkling waters on the market.

Agreed flat water out of a can is… not my favorite.