Poseidon mentions that he kissed Medusa and when Athens found out about this, she turned Medusa's hair into snakes. Since this is a family game, the original rather grim and disturbing version of this ancient Greek myth related by the ancient Roman poet Ovid in his masterwork Metamorphoses was significantly toned down. What Poseidon actually did to Medusa happened in Athena's temple and was quite violent and non-consensual.