Agree with Shark, Ostarine, RAD etc all shut you down and require a proper PCT. Anything that raises your testosterone above normal levels will require a PCT as shit down is just a response to try and balance out elevated levels by cutting production.
PH are just oral steroids but often more liver toxic and Superdrol is definitely one the harshest in terms of sides with lethargy being a major factor. That said Havoc/Epi based PH's are a lot milder. Like steroids, they're not all the same - can't compare Var with Drol!