The biggest name here and probably the least likely considering his popularity, Tyrion Lannister is also the most likely to die because of that very popularity. He is easily the shows favourite character, despite his allegiances to Westeros worst ruling family. Having already avoided death through the moon door in the Eyrie, then that failed assassination attempt at the Battle of the Blackwater, many thought his end would come in what looked like an inevitable battle with the Mountain. However, up stepped the Viper and saved the day, with Tyrion of course escaping Kings Landing via shipping crate soon after. Before then though, he murdered his father and former lover Shae, so now has most of Westeros on his heels. Those chasing him will of course be his sister Cersei, keen on revenge for the death of Joffrey and Tywin. With him heading towards Essos with Varys the Spider, it wont be long before Danaerys catches wind of his presence and demands his head as well, given her hatred of the Lannisters. The show has already shown that popularity does not ensure survivability, just ask Eddard Stark, so Tyrion could be very much heading towards a grim death sometime soon.
