Jiraiya is on his sage mode, but his sage mode isn't perfect, he was not able to properly balance his own chakra with natural energy, and as a result his appearance took on a number of toad-like traits when using Sage Mode: his nose grew bigger and gained warts on his nose, hands and feet, his teeth turned sharp, he grew a goatee, acquired toad-like eyes, and also webbed feets and hands he improved his manoeuvrability