My name is IHyproCritz, of course it isn't my real name. Lol.
Well, I'm "modding" for a while a known Rayman game: Rayman Arena for PS2 (The NTSC version; The PAL version is called Rayman M). I was able to mod it through using MIPS assembly. I discovered several things and created a little ASM Hack(An ASM Hack is a modification of original ASM code of the game. Simple.) for custom weapons. Remember that green bomb from Rayman Arena? Well, I edited it and was able to modify the timer when it explodes.
Currently I'm trying to discover how Rayman Arena loads the levels and such. If I find it out, I can possibly write a Level editor, editing the game objects, placing them (where the weapons should spawn and such) and maybe importing an own Level made in some 3D program of your choice. I'm still not sure yet what 3D format the PS2 console supports, but I will find it out.
What else can I say? Mhh, I have a good experience in MIPS Assembler (for PS2)