MultiMC is a Minecraft launcher. It can be used to launch vanilla minecraft, custom modpacks, or regular modpacks. The launcher is very good for Linux users or those who don't like the Twitch launcher. How to install MultiMC: First you must go to this website and select which software is most appropriate for you. Select it out of these options after the features section. Once you select it a .zip file will install; you must locate the file in your downloads and export it into a folder. Export by right clicking the zip and clicking Extract files.. then select your destination. Wherever you select it will generate a folder there called MultiMC open that folder and your application will look like this. Double click that and launch the app (it will ask you a few things like your language and to select your java version). How to login to your profile: To login click Profiles at the top and click Manage Accounts in the drop down. Then click add on the right side and fill in the requested information. How to allocate more RAM (MUST DO THIS BEFORE SETTING UP AN INSTANCE): To allocate more RAM on the MultiMC you must click settings on your toolbar at the top here. Then go to Java on the left hand side. Under the memory section you will be able to change your maximum and minimum allocation. (Note that I do not suggest going above 6144mb and 4096mb is the average). Should look like this. How to setup an instance with a link: Once the launcher is installed to setup an instance you must find the modpack on the FTB website of Curseforge. Once the modpack desired is located (I will use Age of Engineering as an example) find a button that says download and right click it and select copy link address. It will look like this. Once the link is copied go to your launcher and select the white blank paper at the top that says Add Instance (this). After that a popup should come up and simply click on the check box next to Import Modpack (local file or link) then paste your link into the text box bellow it then fill in the name at the top bellow the image. Should look like this. Then click ok and you should be done! Click on the instance and then launch on the left to begin playing. To update you must reinstall the new update as you did above. Remember to save any world files for single player worlds. How to setup an instance with a .zip file: Once the launcher is installed to setup an instance you must find the modpack on the FTB website of Curseforge. Once the modpack desired is located (I will use Age of Engineering as an example) find a button that says download and install the version of the pack desired. A .zip should install. ONce it is installed go to your launcher and select the white blank paper at the top that says Add Instance (this). After that a popup should come up and simple click on the check box next to Import Modpack (local file or link) then click the 3 dots and locate your zip. Once its located click ok and you should be done! Click on the instance then launch on the left to begin playing. What to do if your archive cannot find instance.cfg: Ensure that you are running the a version 0.6.0 or higher (check you version here). If your version is not 0.6.0 follow this tutorial on how to get it. How to add Java Arguments: Open the launcher and locate the settings tab at the top here in the tool bar. Click on Java on the side here. In the Java Runtime section find JVM Arguments and fill in the blank with the argument. You can then click on Test to ensure everything is working properly. This is an example.