Yorick got a penta

My friend was playing yorick, he had no kills, no deaths, literally first time. A team fight starts everybody dies except him, their tanks are all full health and the adc is low, the supp is the same and their mid is full. He kills them all with aa and q , no ghouls , no ult, just that, and gets his first penta, Vayne was 3.4, gnar was 0.0 and the rest were about 3.2. He kills them all. My question is “How strong is Yorick?”