[1.2.339] Lionheart Castle?

I don't see why it would take so much revamping to do it.

Much of the data that was included in the monsterbook was fully dynamic with mob.wz. The drop tables can be pulled out with a simple query. Considering the complexity of the UI that they use even for basic events, I don't think creating a MB UI would be too bad. The time intensive thing would be to change all of the ETC stuff to have the correct levels. The lore can largely stay the same as well.

So what is it about Monsterbook that would take so long? I'm not seeing it.

Well there is also the possibility they're changing it from the ground up like they did the whole game, plus if the Black Mage screwed everything up, SOME but not all of the lore could change a little.