I am looking for any information on my great uncle who was with the 13th Battalion Royal Fusiliers.
His name was Robert Hay,# 79710... he was killed in action in France, Sept.14th 1918. He is buried (or listed) at Vis-En-Artois Cemetery. I just have panel 3?
Im looking for any information on him or the 13th battalion. He was from Cummingston Morayshire Burghead.
Thank you. 
I also have two great-uncles who served in the 13th Batt. Royal Fusiliers. Edgar Mark Brooks and Arthur Clement Brooks. I have looked without success for service records etc, but a good source of information on the actions that the battalion was involved in can be found in The Royal Fusiliers in the Great War by H.C. O'Neill in various different formats including a searchable pdf here
https://archive.org/details/royalfusiliersin00oneiHis death date of Sept. 14th corresponds with page 306 and I have reproduced a couple of consecutive paragraphs for you which cover the days before and after the 14th. The 10th Batt. was frequently involved in actions with the 13th.
On September 12th Trescault and Havrincourt were taken, and the 24th Royal Fusiliers became involved in the 2nd Division's attack near Mceuvres. An attempt by the 10th Royal Fusiliers to capture the Bilhen Chapel wood switch on the 14th led to one of the most protracted bitter and evenly contested actions of this phase. For the next few days the troops were rested and exercised in preparation for the larger action against the approaches to the Hindenburg system.
Battle of Epehy.—At 5.20 on the morning of September 18th the Fourth and Third Armies struck on a front of about seventeen miles from Holnon to Gouzeaucourt. North of the main attack the 13th Royal Fusiliers were engaged on this day in one of those actions that recurred almost to the very end of the war. The assault was launched in a rain storm, and the battalion found themselves held up by a strong belt of wire.
Looking at the link posted by mmm45 which says he was killed on Sept. 4th the bit you want is on page 303/304 so I have uploaded an attachment pdf of the pages covering the 4th.
Good luck