Making an enemy drop-rate

[Mantoid]

Ok so I want my enemies to have a random chance of dropping items when they die.
I've made it so when they die they're Alterable Value R gets set to random(1000) + 1. Theres a few items they can drop, eg.if they're value R = 100-120, they'll drop a certain item. Theres an item they drop when they're value R = 1000.
Now the annoying thing is, I keep seeing these items appear way too often. Far too many enemies are dropping the rarest item when there should be a 1/1000 chance!
I can't post an example 'cause my game is like 70mb.
My questions are...does anyone know why this might be happening? Or can anyone think of a different way I could make enemies randomly drop items?

[Joshtek]

MMF2 built-in random isn't amazing. Either change the seed often with the "randomize" action or use a dedicated object such as MT Random.

[Syp3r]

I remember making a rain effect (actives randomly appearing on screen) and it followed a pattern.

[Mantoid]

Right ok this MT random object, I don't really understand how to make it work. What do I do with it and what's all this 'seed' buisness?

[FoxBlitzz]

The seed basically tells the program what order to draw numbers in. If you have one seed that never changes, you'll get the same results all the time, and these results are never-ending. Take the Sonic games for example. They actually use a random algorithm to pick which attacks to use next. But they're always in the same order, because the seed never changes.

To make sure you always get different results, you set the seed to the system time. The MT Random object has an option for this in its setup dialog.

[AllistairF]

Try using an alterable value or a hidden counter. If the alterable value could vary up to 1000, you'd have to do a little foresight. When the enemy gets defeated, set the counter to RANDOM(1000). Then decide on a few figures: let's say if the counter equals 27, drop a life-up, but drop an ammunition upgrade if the counter equals 114 or a 1-UP if the counter equals 356 or bonus points if the value is 12 and so on. Any number other than those specified by you would leave no bonus. Although you say that certain cool power-ups are supposed to appear at the odds of 1:1000, realize that sometimes through serendipity, the player gets lucky. I have played Megaman and have seen the game drop a truckload of 1-UP's, but sometimes none at all. It's just luck.