Creep Item dropping problem

How do I make it so that when you kill a creep it sometimes will randomly pick an item and drop it but you won't get an item every time you kill a creep?

I can help you with this. I dont know if you meant it sometimes drops a random item or randomly drops a specific item, so Ill do both.

If you want it to drop a specific item, do the following -

Lets use Footman as an example.

First, create an Integer variable. Preferably, name is DiceRoll (cause I like it :-D)

Now to the trigger:

Events:
Generic Unit Event - Unit Dies

Conditions:
Dying Unit Equal to Footman

Actions:
Set DiceRoll: Random Integer Between 1 and 20
If DiceRoll Equal to 1 then Do Nothing
If DiceRoll Equal to 2, then create 1 Tome of Experience at Position of Triggering Unit

Copy that to raise the chance of it, or lower the DiceRoll

If you want random items at random defeats, make a higher DiceRoll and put more

If DiceRoll Equal to 13, then Create 1 Sword at position of Triggering Unit
type triggers.

Hope it helps~