sarcasm with a very serious tone

Thanks, Uly! "Горький сарказм"?

I’m not sure about the Russian, but the English implies that the tone is so serious that it’s hard to notice the sarcasm in someone’s words.

I see, thank you! Maybe with a hidden sarcasm? I'll think more.

Not so much hidden as hard to detect))

Трудноразличимый)))
Спасибо!

Или едва заметный

👍🏼🤩