I should consider the key elements of a detective game: investigation, puzzles, character interaction, story-driven narrative. The themes of diamonds and simony could lead to a setting where the conflict is between wealth, power, and corruption, perhaps in a high-end or aristocratic environment. Simony introduces a religious or moral corruption angle, which could tie into illegal trades or unethical practices in the diamond industry.

Need to avoid making it too convoluted—keep the themes cohesive. Maybe set it in a fictional city known for its diamond trade, with a history of religious artifacts. The player uncovers a plot where diamonds are being used as currency in simony deals involving stolen relics.

Gameplay could involve traditional detective elements: searching crime scenes, interrogating suspects, solving puzzles related to securing diamonds or hacking into systems. Forensic tools like diamond analysis (detecting fake diamonds, cutting techniques) could be a unique gameplay mechanic. Maybe hacking into corrupt systems or black-market transactions.

I need to structure the feature with sections: Plot and Setting, Core Gameplay, Narrative Structure, Visual and Audio Style, Additional Features, and Development Notes.

For the plot, maybe the player is a detective investigating a diamond heist or illegal trade that's linked to simony—perhaps corrupt religious figures trading sacred relics for diamonds or money. The detective, "Simony Diamond," could be a character with a personal stake, like a history with the diamond trade or a family connection.

I should outline the game's plot, setting, main characters, gameplay mechanics, story and narrative structure, visuals and sound, multiplayer or co-op options (if any), and release information.

Potential for downloadable content, expanding on the world and cases. The game could be announced at a major event, with a release window in a year. Platforms would likely include PC and consoles.

So combining these elements, the user wants a detailed feature description for a detective game that's stylish, intense, involves diamonds and simony themes, and is either innovative or a new iteration. The user might be looking for a game design document or a feature overview for a game that combines detective work with high stakes in a luxurious but corrupt setting.