In my first session with a new group, I played my favorite ranger, Red Creek Rufus and his giant boar pal, Belvedere. We were marooned on an island after a sea dragon took down our ship. As we went about the business of seeing to our basic survival needs, which included doing battle with island denizens, Rufus failed every single roll that session. He never hit. He never succeeded at an ability check. He failed saves. For any spell he cast that had a saving throw (animal friendship, for example), the monsters made their saves.
In subsequent sessions, his luck has improved, but I decided after the first session to essentially play him as the Worst Ranger Ever. He makes up stuff about monsters the party faces, giving them strange names, drawing the wrong conclusions about their abilities. When someone questions him, he makes an argument from authority - "I'm a ranger, I know these things."
His lack of luck continues in one particular area consistently though - communicating with animals. Whenever the party comes across some monsters in the forest, the running gag is the party sends Rufus forward to communicate with them. He does some strange gesticulating and animal noises, occasionally tries an animal friendship spell, and inevitably everything goes awry. "Rufus turns around to face the party with a concerned look in his eye and shouts, 'Run!'" is how most of our combats start out!