Easiest FPS editor to create a Total Conversion?

[morguerapist]

First of all, I haven't attempted this since tinkering around with the original DOOM and making several really nice levels. Recently I have had the urge to create an FPS that's really nothing more than an exorcise in depravity and if I'm successful, I'll go on to create something hopefully unique and original (haha). I have a really interesting idea in my head and I'm considering using POSTAL 2 as a framework. I've been screwing around with UnrealEd: Postal 2 Edition but I'm not sure this is best for my idea.

So can anyone recommend a relatively easy FPS editor to learn? I'm not interested at all in top-end graphics, physics, whatever, just whatever's easiest, provides a bit of freedom and gets the job done.

Ideally, I'd like to create an topdown action game with RPG elements. Are there any games out there with editors available like this?

Thanks.

[Pandemic]

Well theres 2. FPS creator is good for total noobs. Just drag and drop and you can code extra stuff too. for more advanced id use the source engine and source SDK

[Chevalr1c]

I guess you mean with "topdown shooter", the looks of for example the old GTA (1 & 2) parts? Or do you want to do it Doom-style, thus "3D"?

In case of first-mentioned, try out Game Maker (http://www.yoyogames.com/gamemaker). But be aware that you cannot make a mod then, it is a simplified game design and programming (drag-and-drop) program. So in that case you will have to make the game yourself (from scratch).