Is it possible to use the "-" search modifier (if that's the right word?) in the blacklist, to the opposite effect? As in, I blacklist "Pokemon" but then blacklist "-Lucario" so I DON'T see the majority of posts containing "Pokemon" but I do if they contain "Lucario"

Yup, you can - It would look like this.
pokemon -lucario

Thank you! I thought that's how that worked, but wasn't sure. Much appreciated.

Note that right now anything aliased that uses - currently doesn't work. So if you did male -pokemon it wouldn't work because pokemon is actually aliased to pokémon (male -pokémon will work fine though).

Oh, also it's worth mentioning that the exact meaning is a bit different depending on where it is. For instance:

• mammal - Blacklist all posts tagged mammal
• -mammal - Blacklist all posts that aren't tagged mammal
• mammal male - Blacklist posts that are tagged with both mammal + male
• mammal -male - Blacklist all mammal posts, but allow ones that are also tagged male
• -mammal male - Blacklist all posts not tagged with mammal + male (searching for -mammal male should show 100% block rate)
• -mammal -male - Blacklist all posts not tagged mammal + male (searching for -mammal -male should show 100% block rate)