A suggested modpack for Weeblee's Bizarre Adventure Pixelmon server.
Then the are some helpful things such as Journey Map fore getting the lay of the land and not getting lost, and Pixelmon Information for Pixelmon Reforged (that works with JEI and HWYLA), that allows you to figure out learn and craft Pixelmon items (JEI alone can't do that sadly), determine what Pokemon drops what, and some basic Information on the Pokemon when you look at them.
Lastly, there are the mods FTB Lib., and FTB Utilities that allows you to make and manage teams, claim areas and a few other little things.
Just go download Pixelmon Reforged, and put it in the mods folder and you are good to go.