They have a vat of boiling oil, which is just about tipping to the brim and aimed at the merry intruders.
[I]t is often implied that the trend of the vat is continuously upward.
And, also, there ought to be no other forms of taxation, like a national sales tax or a vat tax or what have you.
early 13c., southern variant (see V) of Old English fæt "container, vat," from Proto-Germanic *fatan (cf. Old Saxon, Old Norse fat, Old Frisian fet, Middle Dutch, Dutch vat, Old High German faz, German faß).