HI Patrick,
List operation Sort your list in descending order as per date or any ordering field then take head from that list .
If you don't have any ordering attributes then take aggregatelist count of list, also create one counter variable value as 0, iterate the list check the condition counter = count-1 then continue else delete the iteration list object.
By using change list activity you can add object at the end.
Hope it helps!
Thanks & Regards,
Manikandan K