Black Knife Simulator focuses on a battle where preparation can be just as important as reacting to enemy attacks. Based on the Roaring Knight encounter from Deltarune Chapter 3, this fan-made game allows players to control Kris, Susie, and Ralsei during a confrontation with a sword-wielding opponent. The battle combines command-based combat with projectile-dodging mechanics. There is no separate storyline or world to explore, as the simulator recreates a single encounter with several optional difficulty settings.

Deciding How to Face the Knight

Before beginning the fight, players can change the battle conditions by selecting a Shadow Mantle configuration. The mantle provides protection against certain attacks and can be assigned to different party members. Choosing who receives it affects how players manage incoming damage. Additional challenge settings introduce restrictions, such as fighting without healing or attempting to complete the encounter without being hit. These options make it possible to approach the same battle using different strategies.

When the Arena Becomes an Obstacle

During defensive turns, players control a red SOUL inside a battle box. The Roaring Knight attacks using sword-shaped projectiles, rotating blades, and patterns that restrict movement. Some sequences divide the available space, forcing players to reposition before another attack begins.

The encounter includes:

•         Turn-based commands for Kris, Susie, and Ralsei.
•         Different Shadow Mantle assignments.
•         Optional challenges with additional restrictions.
•         Projectiles that track the SOUL’s position.
•         Rotating swords and moving blade formations.
•         Attacks that divide or narrow the combat area.
•         Health management, healing, and defensive actions.

Learning the Sequence of the Fight

Players use the arrow keys or WASD to navigate menus and move the SOUL. Press Z or Enter to confirm commands, and X to cancel selections. Holding X during defensive sequences allows more controlled movement through narrow openings. The C key advances dialogue, while number keys 1–7 select battle configurations before the encounter starts.

Black Knife Simulator does not use numbered levels or a system of unlockable equipment. Progression consists of surviving successive combat turns as the Knight introduces different attacks. The encounter follows a scripted sequence rather than an open-ended survival format. Players can restart to practice particular patterns, experiment with mantle assignments, or attempt more demanding restrictions. Completing the battle requires managing party health, understanding projectile movement, and choosing appropriate defensive actions.