after dealing with the reaper leviathan and upgrading your sea moth nice you have lasers now so you decided to go into the void you find some ghost leviathans but then you hear a big movement in the distance and a big roar much bigger then the reaper leviathan roar after that you saw it the gargantuan leviathan its body was SO DAMN LONG it was like 5.2 kilometers long! After that it became aggressive so you gotta run away or you can just dodge or something like that have fun