With the introduction of Alpha 17 experimental, the concept of a modlet was introduced. Modlets are smaller mods that don't over-write the vanilla XML files, but are loaded from the Mods folder.
A typical modlet would have the following format.
SphereII_PG13/ Config/ ItemIcons/ Resources/ ModInfo.xml
Not all modlets will have the different folders; it really depends on what the modlet does. For example, a XUI modlet wouldn't necessarily have an ItemIcons or Resources.
However, all modlets will have a ModInfo.xml
Modlets are installed the same on Client as they are on a Server.
1) Create a folder called "Mods" at the top level of the game folder.
2) Download the modlets you want.
3) Extract the modlet, and look for the ModInfo.xml for each mod you want. Once you find that, copy the folder into the Mods/ folder.
Do not copy the contents of the folder, but rather the folder that has the ModInfo.xml
In the above example for the SphereII_PG13 modlet, we would copy the SphereII_PG13 into the Mods folder.
You can review the output_log.txt to confirm which ones are loaded.
The following has three modlets being loaded:
2018-11-26T21:51:46 1.901 INF [MODS] Start loading 2018-11-26T21:51:46 1.902 INF [MODS] Trying to load from Guppycur_BloodMoonTrickle 2018-11-26T21:51:46 1.930 INF [MODS] Loaded Mod: Guppycur's BloodMoonTickle (1.0) 2018-11-26T21:51:46 1.930 INF [MODS] Trying to load from SphereII_PG13 2018-11-26T21:51:46 1.931 INF [MODS] Loaded Mod: SphereII_PG13 (1.0.0) 2018-11-26T21:51:46 1.931 INF [MODS] Trying to load from SphereII_RainUI 2018-11-26T21:51:46 1.931 INF [MODS] Loaded Mod: SphereII's RainUI (2) 2018-11-26T21:51:46 1.931 INF [MODS] Initializing mod code 2018-11-26T21:51:46 1.931 INF [MODS] Loading done
The folder structure of the above log:
Mods/Guppycur_BloodMoonTrickle/ModInfo.xml Mods/SphereII_PG13/ModInfo.xml Mods/SphereII_RainUI/ModInfo.xml