schema.gql

type Query {
  deity(name: String): Deity!
}

interface Character {
  name(id: ID): String!
}

interface Supernatural {
  power(id: ID!): [String!]!
}

type Deity implements Character & Supernatural {
  # arg id has stronger type
  name(id: ID!): String!
  # arg: has same type
  power(id: ID!, age: Int!): [String!]!
}