and welcome. To make a character "invisible" use the setalphafade=x command. Since you have some experience with fpsc first look at your characters appear
scripts ( appear1 & appear2 ) Note the use of the command setalphafade in the appear2.fpi script. See how it goes from 0 to 100. That means it "fades in" the characters texture/appearance.
So in the characters Main Ai script you can set its alpha fade to something you want.
Another method is to use the Alt-texture command. All entities can have an alternate texture ( it can be a blank/tranparent texture to mimic being invisible ) The alttexture can be triggered
with a simple key press command, action or anything you want.
If you want to have the ability to "adjust" its transparency then the alphafade is a better solution.
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