Start with Ad Noctum: Dynasty of Death. If you like the aggressive aspect of that album, then go forward and get The Ultimate Death Worship and then the new album.
If you like prefer the keyboard/symphonic aspects of Ad Noctum more, then go backwards and get In Abhorrence Dementia, Moon in the Scorpio and, if you can find it, Epitome of Illusions.
Judging by your avatar I would suggest the first approach (especially if World ov Worms was your favorite as that has Limbonic Art's vocalist on it).
Welcome to Limbonic Art. I guarantee your investment will pay off well to your liking.