NuMord

Myself and several others who has mained Mord before his rework has been dissatisfied with the outcome. However a good number of reasons may not be as in your face obvious like damage or aesthetics. One of the main reasons why I dislike NuMord so dissatisfying is that he is now extremely linear. I dont mean Linear as in there being an optimized way of playing but more so that there is only ONE way of playing him.

For example, there is absolutely no reason why you should not take the recommended rune pages as in Precision/Conq Primary and Domination/Ravenous Hunter secondary. Its not because its extremely good on him but because that is his only usable options. This is because of his mechanics and scalings which also affects his build variety. He scales purely off of AP so he can only build AP items. He's an AP Darius but somehow a lot more linear. It also doesnt help that his main damaging ability being his Q and passive is so micromanaged that it doesnt feel good. Even his Ult is a bunch of meh.

In comparison with Old Mord, he has both AD and AP scalings where both of which arent bad. More importantly is how his old Q worked dealing a ton of damage on the 3rd hit. This allows him to build some AD items to enhances his 3rd hit and even some Attack Speed items to allow him to get that 3rd hit much quicker. His E also scaled off of AD that gives him the leeway to prioritize AD if he so choose to do so. This opens the path way to many different and viable builds. You could go HoB for those instant Qs, Conq, or even Grasp since it synergies well with his Shield passive.

Old Mord may be slow and immobile but felt a lot more impactful and satisfying than NuMord. However I do feel that you can successfully mix in his old with the new without leaving out things on what makes people like from either versions.