There are two kinds, the concepts for each theme are as follows: Material UI replaces FFXIV's built-in theme (dark-theme) Yoshi P interview for more context on this matter: INTRO The first rule of mods, is don't talk about mods. Square Enix has a much lower tolerance for nsfw mods and will aggressively take down anything that is not 'brand safe' There are a few rules of thumb when it comes to third party tools. Some tools, like combat trackers, are abused to harass other players while others have a lewd/illegal nature to them, and so Square Enix must be able to ban accounts who use modding for this purpose. It is a complicated, grey-zone issue that usually ends in circular arguments and it just never ends. However, Yoshi-P (the game's producer) has said in interviews that while the official stance on third party tools will always be 'no', Square Enix both cannot and do not want to see what is installed on your PC.
Using third party tools for FFXIV is against the Square Enix User Agreement, and should be done at your own risk as it could result in an account ban.
