It isn't a typical reaction to a ward, but this is not a typical rune.

[ Of that much Istredd is certain, which is why he asked for help in the first place. Himeka's head and her arms are mostly free now which means she can help scoop herself out too, but it's best to get as many hands as possible. If Geralt and Lucifer helped instead of watching, this would already have been over. ]

I'm afraid you're going to have to get dirty and help dig her out of here. We'll figure out how to wash off after.

[ She's surrounded by the substance and that's the only way out. Istredd is already covered in it himself, but at least he knows this is temporary clothing. Unfortunately, it'll be Ikorr who has to deal with it later. ]