The reason this build works is very simple. Since you are fizz you are very mobile and with this build you become a tank who is very mobile can slow you knock you up and do damage to you which becomes very frustrating to the enemy team and to kill you it will most likely take most of the enemy team leaving your carries to do damage and if the enemy team tries to focus your carries you can either peel for your carries or kill the enemy team.

Most likely you will want to start at the buff bot side (depending on your side of the map) so you will have 2 people leashing you therefore making your early clear slightly better than it would be if you started top side. If you start blue buff than i would suggest going grump and than scuttle and from there you could either go wolfs or chickens and than depending on your health either go to the other scuttle (if there) to regen some health with hunter's machete or go red and than back. if you start red side do the same except insted of grump after red go krugs and basically its the same clear after that.