I have fought many rare bosses. Not everyone fights these. These bosses are really rare. One day I fought two rare bosses in Pardes Del Fuego. If you want to fight rare bosses try these servers Legassa or Tortos. The rare boses really give you good rep and loot. They might be easy for high levels like 50's or 30's. I saw some rare bosses in the invasions and to be honest with you, they are harder to fight. Even harder boss is Jolly Roger everyone knows that. And even harder is Foulberto Smasho. Devil Root plus El Patron combined is as strong as Jolly Roger. Jolly Roger plus Devil Root plus El Patron combined is about as strong as Foulberto Smasho.