Scurrilous, satirical poem e.g. John Wilmot's famous epitaph for Charles II:
[n] a composition that imitates somebody's style in a humorous way
[v] ridicule with satire; "The writer satirized the politician's proposal"
burlesque, charade, mockery, parody, pasquinade, put-on, satirise, satirize, sendup, spoof, takeoff, travesty