I don't know if this is possible, and if it isn't, it would be a good idea to implement. Let's say someone doesn't like MLP. So they blacklist the "mlp" tag. But they DO enjoy anthro mlp, so you should be able to add a "blacklist cancelling tag" that would make posts with blacklisted tags show up as long as the have a blacklist cancelling tag.

Adding

my_little_pony -anthro

all in one line will do the trick.

Also nice username

Fluttershy is right, you can customize your blacklist by adding lots of combinations of blacklisted tags and negating tags (tags that start with -)

What Fluttershy said, but to elaborate a little, a - before any tag means basically "without x", so any mlp posts without the anthro tag will be blacklisted.

There are also quite few other neat things possible, have a look at this and this.

Anything that works for searching will work in the blacklist as well.

A fairly easy trick to figuring out complicated blacklist rules: Play around with the search bar on the site until you get a set of search results that you DON'T want to see. Then add that exact search to its own line of the blacklist. A line on the blacklist means "any posts that show up in this search will be hidden". That's why you can negate tags in the blacklist to show them again; it prevents them from showing up in the search, so they won't be hidden.

Note that you can't use most meta-tags (tags with a : )in blacklists (score:, fav:, etc.).

NotMeNotYou said:
What Fluttershy said, but to elaborate a little, a - before any tag means basically "without x", so any mlp posts without the anthro tag will be blacklisted.

There are also quite few other neat things possible, have a look at this and this.

Anything that works for searching will work in the blacklist as well.

Actually most meta tags, your either or (~cat ~dog) and order:score, order:favcount, etc do not work in the blacklist

Only individual post id's, ratings and user id's work

Rainbow_Dash said:
Actually most meta tags, your either or (~cat ~dog) and order:score, order:favcount, etc do not work in the blacklist

Only individual post id's, ratings and user id's work

Well of course either or doesn't work for blacklists; cat and dog on separate lines suffices; Just double the other tags involved.

123easy said:
Well of course either or doesn't work for blacklists; cat and dog on separate lines suffices; Just double the other tags involved.

No meta tags work on the blacklist, not just either or. I mentioned it anyway as that's not really a meta tag