Here is my walkthrough for the game Endless Zombie Rampage in Survival mode.
Buy the FN Scar Assault Rifle.
You just spent 5000 Exp.
Click the Power ups tab at the top.
Buy 250 Base Hp (2500 Exp) Buy 25 Base Hp 6 times (200 Exp each, 1400 Exp total) Now you have 500 Base hp.
its really Important to Protect your base, as it dies Fast.
Buy 100 Hp for you (1000 Exp) Buy 10 Hp for you 4 times (100 Exp each, 400 Exp total) Now you have 155 Hp, and your base has 500.
Now you have 0 Exp, Alternatively, if your not happy with the FN scar, you could always buy the Desert Eagle wich is 4000 Exp, and saves you 1000 Exp for Four lots of 25 Base hp (600 Base Hp total) then spend the remaining 200 Exp on Your hp (175 Hp total)
the Desert Eagle has 30 Shots and 1 second of reload time, and it does 100 Damage, the highest damage out of all the weapons, the laser cannon does the same damage.. but it has 1 shot and 2 second reload, Waste of Exp.
Anyways, Start the Game.
The Key to Winning is Protecting your base, with my Walkthrough, your bound to make it past 300 - 800 Kills, which is good! usaully the Daily highscore is 350 kills - 700 kills.
When the game starts, go Ahead and just go out there and kill all the zombies, should be no problem, just be careful not to let them slip past you and to your base... after around 20 kills, go back to your base, and wait, after around 50 kills, the red zombies should be apearing, wich are very dangerous, they can destroy your base in seconds! killing them is a top priority, but be careful! watch your back and not just your base!
After 200 kills, its going to get pretty chaotic, Swarms of red Zombies, but with the FN Scar, or Desert Eagle, should be no problem until you hit 300 kills, then it starts to get really tough, just keep guarding your base and dont let the zombies get you!