I’d like to make a bold variant for my font, but I would like it to apply to only certain glyphs. Is there a way to make the bold variant affect only selected glyphs, or does it transform the entire font?
If you did a stylistic alternative for just the glyphs you want to embolden then it could be done that way.
Thanks. This part of it is totally new to me. Could you direct me towards a tutorial or support page?
You don’t need any OpenType features for this. Just use the glyph transformer to embolden selected glyphs, not the whole font, and let it change the font flags to bold weight. When the word-processor uses bold text, the bold variant will be used. The glyphs that are the same weight in both fonts will not look any different, only those that you have transformed.
That is a simpler solution. 
Thanks, but using the bold transformation does not give me the exact result I need. There are dedicated bold characters that I wish to simply substitute, so when user switches from Regular to Bold, those selected characters will be bold, but others will not.
Well, that is exactly what will happen if you do as I said.
When a user selects bold in a word-processor, the bold version of the font is automatically selected. If you only apply the glyph transformation to the characters in the bold version, the other glyphs in the bold version will still be regular.
Regular 
Bold The rocket glyph is the same in both regular and bold versions of the font used here.
OK, I think I understand… I have to flag a glyph as “bold,” and it will use the bold variant I’ve assigned. Thanks!
You have to create a bold version of your regular font that is identical, except for the glyphs that you wish to be bold.