When you position backdoor the enemy team when you go in while your team goes in come from behind and ult the all this will grant you a major shield and a win in the team fight. Play Video
In this video Eveylnn shows a perfect display of positioning she goes around and comes in from behind therefore giving her a penta kill.When you do this you can spray the key targets in the back Such as Ap/Ad carries. This will help your team win games.