The MCMultipart is a core mod of amadornes and is required to make various other mods work. In itself, the MCMultipart Core mod does nothing and adds nothing to vanilla gameplay, and installing it independently will not affect the game.
What the Mod Offers
Core mods don’t offer anything in the vanilla game unless other mods use their content. The MCMultiPart mod provides frequently used and highly-optimized codes and resources, making it valuable and easy for other mod developers.
Should You Install It?
Other mods need core mods. If, however, you do not wish to use any of the mods that require the MCMultiPart mod, then it’s better not to install it.