Beating Saxon Hale The Hardest Boss
My two favorite classes in this mode are the scout and pyro because of there similar but also different play styles. The scout tries to out maneuver the boss at a close range with his speed and double jumps, while the pryo also stays at a close range but does a mix of burning him and air blasting him away.
Scout
My set-up as a scout is a Force of Nature and Winger and a Atomizer and a grapple hook (if the server allows it). With this build you will find it easy to juke the boss with your movements. Lets start with the primary, i go for a Force of Nature due to its knockback properties applying it not only to the boss but also to you making it a great way to get distance and deal some damage. I choose the winger and atomizer because the winger boost your jump height by 35% which with pair with the atomizers ability to give you 3 jumps lets yo scale the boss. The pyro only requires a basic flamethrower however, with a simple combo of left and right click when the boss gets close.
The other two most viable classes are the solider and heavy. At first they both seems to have nothing special, but the solider has better movement than a scout and the heavy, paired with a team, can destroy the boss in a matter of seconds.
Solider.
As the solider i prefer the Rocket Jumper, the Reserve Shooter and The Market Gardener. This combo revolves completely around your ability to rocket jump so if you can do it this wont work for you however if you can do it with your eyes closed then this should be a reliable way to kill almost any boss. The rocket jumper is used to get your way around the boss and to propel you in the air, while in the air you pull out your Reserve Shooter and blast him since it does more damage in the air than on land, and while you land down get you market gardener and smack him then jump up again.
Heavy
Heavy is super simple, all you need is a trusted medic... or two. The heavy does not shine on its own, I would consider it to be one of the worst on its own. However if you have a medic who knows what he is doing then you can kill the boss in a matter of seconds. All you need is a Brass Beast, once you have one let the boss come to you let the medic uber-charge you and you have won.