I got a 66% on an exam at uni that I did *no* revision for (basically) where I thought I had failed, plus I had finished and written everything I could 30 minutes before the exam actually finished. I finished so early that I drew the most elaborate comic strip on the back of my question sheet that made the invigilators stop and stare. I remember I was bull****ting like crazy and writing facts that didn't even answer the question, but apparently the examiners were high on something when they were grading my work because they thought it deserves a relatively strong 2:1 grade lmao