Ishanail's base of operations can be found on the East side of Rogueport. Under his influence, the East side is far less secure than the West. It is unkempt, dirty, and serves as a hiding place for many bandits. His guard Gus even demands money for entering the further part of the East side. The West side is on the contrary, rather secure and clean.
On his quest for a Blimp Ticket, Mario needed Ishnail's help on how to visit Don Pianta. For 64 coins, Ishnail informed him that he needed to buy a Dried Shroom, followed by a Dizzy Dial, in Peeka's shop, a secret sign known only to friends of Don Pianta.