question: How many games in the Halo series feature Master Chief as the main character?
answerText: 4
questionEntity.name: Q1747150
questionEntity.entityType: entity
questionEntity.label: Halo
questionEntity.mention: Halo
questionEntity.name: Q652022
questionEntity.entityType: entity
questionEntity.label: Master Chief
questionEntity.mention: Master Chief
answerEntity.name: Q276217
answerEntity.label: Halo: Combat Evolved
answerEntity.name: Q252804
answerEntity.label: Halo 2
answerEntity.name: Q137802
answerEntity.label: Halo 3
answerEntity.name: Q45028
answerEntity.label: Halo 4