Xxl pros uses Credits in their Server. With Credits you are able to buy Cool stuff.
Now, i will give you some hints.
Type /buy to buy stuff.
/credits shows how many credits you have at the moment.
Now some buying hints.
Check item upgrades. Then buy First Aid. Now you armor/hp will start to regenerate and you will be MUCH more harder to get. I suggest that you get a M4 and start to kite Zombies.
What is kiteing?
Kiteing it that you run around in one place and shoot zombies meanwhile. Yes, it is pretty hard but with some training it will be pretty easy. And with First Aid, zombies must get rid of your armor first. This means that you can handle 100 dmg before you are in trouble.Back to item upgrades.
Buy climbing gear. This allows you to climb walls with pressing jump or forward. Very useful, it allows you to hide in places, where you cant go without it.
Passive upgrades.
Armor 0-5: Increase your Armor (useful with First Aid!!!)
Health 0-10: Increase your HP. (Useful with First Aid aswell.)
Speed 0-6: Increase your speed. (Do the Gingerbread run!
)
Gravity: Forget about this. (if you are not admin in the server!)
Stealth 0-6: Makes you a bit more harder to see. It has some use...
Multi-jump 0-6: Very useful with anything. Allows you to jump in air the many times you have spend credits in it.
I hope this will help you.