I have seen many of people complaining about RAZE's 26th level. I still have yet to beat it myself, but I have gotten 1-3 kill left many of times. Below are hints that will help you if you can't get close to winning.
~Aim for the human, unless you see a robot with little health. ~Don't chase a robot with a Railgun. ~Try to get the 2x damage modifier at the top. ~Don't die because I notice that most of my team's deaths are from me. ~Keep the Railguns away from the enemy because they kill you in one shot. ~Keep your cursor near your player because you will get less lag. ~Pick up the health packs on the top corners in the elevators, even if you don't need them because the enemy will use them. ~Try to dodge grenades because these kill you in one shot 95% of the time. ~Try to combine the Grenade launcher or the Railgun with the 2x damage multiplayer. ~Try to back up teammates with low health if they are being shot at by an Uzi. ~Use your best weapon. Note: You also need to have good aim to.
If you have, any other hints feel free to add them to the list. I will add more if I find some. Last, add feedback about hints for level 26.
SURVIVE. Given the choice between finishing off an enemy and running, RUN. Shoot while running, but run away.
Wherever you are, whatever you are doing, if you see a Robot. RUN. It's just not worth it.
Hang around the corners of the map (i.e the elevators) [*]
If you see an enemy, immediately start bobbing and weaving. It'll often buy you enough time to run away, which is the whole point.