What does this status icon mean?

I noticed that when standing in some water pools in chalice dungeons, this icon appears under healh bar where boosts from gems usually are. I don't think I've seen it in story mode. Gems I have in weapons just increase physical attack. I checked character screen, but resists and stats seem to be unaffected, if I didn't miss anything. And it's not poison.

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Does someone have an idea?


Solution 1:

I am 99% sure it means you are oiled and therefore susceptible to fire attacks. There are definitely areas where you are standing in neither water nor poison. And oil is the next logical step.