Player enjoyment

1. Player Identification vs Player Authentication (Gamification Achievement Systems Tips)
2. Player Proficiency vs Player Competency (Gamification Player Progression Tips)
3. Economic Constraints vs Game Constraints (Virtual Economy Gamification Tips)
4. Player Advancement vs Player Improvement (Gamification Player Progression Tips)
5. Game Revenue vs Virtual Revenue (Virtual Economy Gamification Tips)
6. Game Update vs Game Patch (Player-Centric Gamification Tips)