Opus Castle

First-person horror adventure with branching stories in a haunted castle

Messier Games · Published by QUByte Interactive · Released Nov 9, 2021

Reviews: Mixed; 59% of 99
Recent reviews: Not enough recent
Players: 0; daily peak, Oct 28, 2026
Steam Deck: Untested
Last update on Steam: 1 year ago; May 30, 2025
Minimum PC: GTX 670; Full requirements

What is Opus Castle?

In this first-person horror adventure, you wake beside a bullet-riddled body in São Paulo's Castelinho da Rua Apa. You explore the castle's rooms and encounter apparitions and unexplained sounds in a chapter-based story.

For you if...

+you enjoy psychological horror centered on exploration and storytelling

Not for you if...

−you prefer open-ended wandering to following a set path

What players say

59% of 99 reviews are positive

Players praise the mystery's connection to a real Brazilian crime. They criticize awkward controls and unclear guidance, and describe the free opening as brief, with the rest of the story requiring paid chapters.

Screenshots and trailer

Opus Castle system requirements

Minimum: GTX 670.

As published by the developer.

Can my PC run Opus Castle?

Tell us your graphics card once and every game page will answer this for you.

Set up my PC →

Minimum

OS: 64-bit Windows 10
Processor: Intel Core i5-750, 2.66 GHz / AMD Phenom II X4 965, 3.4 GHz or AMD Ryzen™ 3 1200, 3.1 GHz
Graphics: NVIDIA® GeForce™ GTX 670 or NVIDIA® GeForce™ GTX 1050 / AMD® Radeon™ HD 7950 or AMD® Radeon™ R9 270
DirectX: Version 10

Does Opus Castle have co-op or multiplayer?

No: single-player only, no multiplayer modes declared.

Single-player

Does Opus Castle run on Steam Deck?

Untested Not yet tested by Valve on Steam Deck.

PC version details

DRM: None declared on Steam
Controller: Keyboard and mouse
Platforms: Windows
Achievements: 39
Steam features: Cloud saves, Family Sharing
Languages: Full audio: Portuguese - Brazil. Text only: English.

Does Opus Castle use AI-generated content?

No AI-generated content is disclosed on the game's Steam page.

Self-reported by the developer under Steam rules: it covers AI content that ships in the game, not tools used to make it. Steam page checked on Oct 27, 2026. How to filter AI games on Steam