Looking for any suggestions that have a protagonist that uses an assumed identity to get their revenge, preferably by getting close to the people who wronged them. I don't care at all what the genre is as long as there's tons of dramatic irony!

Bonus points for:

• behind the scenes politicking
• getting revenge through means other than straight-up murder
• the MC angsting about whether they're doing the right thing

And yes, I have definitely already seen Gankutsuou and loved it a lot.

Other manga I've read that fit the bill more or less: Alfheim no Kishi, Ubel Blatt, Basara

Akumetsu, Azumi, Berserk, Blind Faith Descent,
Destroy and Revolution, Fire Punch, Gunnm (eventually),
Ikigami, Innocent (SAKAMOTO Shinichi), Joou no Hana,
Jojo no Kimyou na Bouken - Jojorion, Kami-sama, Ki-sama o Koroshitai.,
Kento Ankokuden Cestvs, Kurosagi - The Black Swindler, Oldman,
Shingeki no Kyojin (it´s complicated), Toukyou Kushu (eventually) and Vinland Saga.

Read the actual Monte Cristo novel too, it´s HIGHLY different.

I also read EU/US comics and am a librarian.
Manga-Masters, My ANN-Lists + Imdb

@residentgrigo: Thanks so much for the recommendations!

And the actual Count of Monte Cristo novel is one of my favourite books so I've read it a ton eheh. Nothing quite scratches the dramatic-irony-slowburn-revenge plot itch as much as the original does but I'm always happy to read new variations on a classic.

residentgrigo has mentioned almost everything I had in mind, but I managed to think of a few more:

Akusaga might not look like it fits at first, but you have to keep reading until the end to see the truth. It fits best out of everything I've mentioned, imo.

Kokuhaku fits better in a way (revenge through means other than murder) but is only one volume long and has a narrow scope.

Kisshou Tennyo is longer and the revenge more drawn out, but there's a fair number of deaths involved, though the protagonist doesn't commit them herself.

Ayeshah's Secret, Banana Fish -- But they do have a lot of killing.

Banquet Box, Ningen Gakubu -- Not completely scanlated, unfortunately.

Conductor, Duds Hunt, Akumu no Elevator -- Once again, not obvious at first, but keep going.

Giniro no Kami no Arisa, Sasori -- Very classic revenge fantasies.

Some of the master/slave pairs in Doreiku - Boku to 23-nin no Dorei

Arisa might fit, but it's been a long time since I read it, so not entirely certain.

None of these titles except Akusaga involve any large-scale politics, sadly, though Kisshou Tennyo does have the olden-day Japanese main family-vs-branch family style of politics. The protagonists aren't at all sorry about what they do, either (though I must admit I prefer it that way, since the alternative is usually that they fall for one of the people who wronged them).

@celstine: Ah these all look really promising, thank you so much! I appreciate the little write-ups about each as well.

And It's totally okay if they don't check off everything I mentioned, good old-fashioned revenge + secret identity plot is really all I need and the rest is just bonus ahah.

A few that haven't been mentioned yet...

7th Garden
Blade Note
Fukushuu Kyoushitsu no "secret identity" in this one
Shut Hell

All are the murderous flavor of revenge.