I defeated Diablos and Barioth offline on my onw, Maxi. As for Rathalos, I am still having trouble beating him, but I plan to focus on upgrading my Rathalos armor before I take him on again. I still do not have Rathalos armor for my arms because I need a Rathalos plate. However, I decided to buy a Rathian arm armor to take its place temporarily until I can figur something else out for the time being.