Gerson Fight — Hammer of Justice

How to Play Gerson Fight

To begin playing the Gerson Fight, you must first wait for the application to fully load in your web browser. Once you see the title screen, click anywhere inside the game window to ensure that your browser grants it keyboard focus. After securing focus, press the Spacebar to start the full playable demo. You will immediately be thrown into an intense encounter where you control Susie, acting entirely on her own without the rest of the Fun Gang to support her.

The gameplay follows the traditional Deltarune battle system but with a heavy emphasis on defensive mechanics. During your turn, you can navigate the familiar combat menu to select actions like FIGHT or DEFEND. Because this specific fan-made recreation is currently an in-progress demo, certain menu options like ACT, ITEM, or SPARE may exhibit developmental bugs or incomplete functionality. Your primary goal is to progress through the available combat rounds by effectively utilizing your offensive strikes and defensive positioning.

When Gerson initiates his counterattack, the battle transitions into the defensive phase. You will primarily utilize a modified Green SOUL mechanic. Instead of moving around a traditional bullet board, Susie remains anchored in the center while holding her axe as a shield. You must press the directional keys corresponding to the incoming projectiles to block them before they strike her. The battle requires immense concentration and rapid reflexes, pushing you to survive through approximately seven distinct rounds of escalating difficulty to complete the current demo sequence.

Controls

About Gerson & Hammer of Justice

Gerson Boom is a beloved and highly significant character within the overarching narrative of the Deltarune and Undertale universes. While veteran players remember him as the wise, elderly shopkeeper in the original Undertale, his presence in Deltarune is deeply woven into the town's history. In the events leading up to Deltarune Chapter 4, his Darkner incarnation manifests as an imposing Old Man figure. This character eventually reveals himself as the Hammer of Justice, an incredibly formidable opponent who serves as the secret Shadow Crystal boss for that specific chapter.

What makes the Hammer of Justice encounter particularly unique is the narrative framing of the battle. Unlike most major boss fights in Deltarune where the player controls the entire party simultaneously, this confrontation forces Susie into a solo fight. This isolation is a critical moment for her character development, forcing her to rely on her own defensive capabilities rather than leaning on her teammates for support or healing.

This web-based browser application is a dedicated fan recreation developed by mario3d190. It allows fans to experience the visual spectacle and mechanical challenge of the Hammer of Justice fight without needing to wait for official releases or download heavy modifications. By isolating this specific encounter, players can focus entirely on mastering the unique defensive mechanics that define Susie's solo combat capabilities.

Gerson Fight Mechanics — Green SOUL, Blocking & TP

The core gameplay loop of the Gerson Fight revolves around the highly specialized Green SOUL mechanics. When comparing the original Deltarune Chapter 4 concepts to this playable browser demo, it is vital to understand what has been implemented. In this recreation, the Green SOUL anchors Susie to the center of the battle box. She wields her axe as a heavy directional shield. Your objective is not evasion, but interception. You must press the directional keys (Up, Down, Left, Right) to pivot her axe and block incoming magical hammers and projectiles.

As the rounds progress, the blocking mechanics become significantly more complex. The game introduces diagonal blocking, requiring you to anticipate attacks originating from the corners of the screen. In the original design, perfecting these blocks allows Susie to accumulate Tension Points (TP). This demo has successfully implemented a working TP system and the DEFEND command, allowing players to build resources strategically by timing their blocks correctly against the rhythmic assault of Gerson's attacks. Some projectiles, specifically the shell attacks, possess a bounce mechanic, meaning a single successful block might not eliminate the threat; you must be prepared to intercept it multiple times as it ricochets.

Furthermore, the battle is not exclusively limited to the Green SOUL. Certain heavy hammer attacks possess the ability to forcibly transition the player back into a Red SOUL state, stripping away the stationary shield and forcing Susie to rely on traditional free-movement dodging. While the original official encounter features complex interactions where Gerson deflects Susie's Rude Buster magic (requiring a precise counter-deflect timing minigame), players should note that this specific browser demo focuses primarily on polishing the foundational Green SOUL defense and standard FIGHT progressions.

Tips for the Hammer of Justice

• Secure Keyboard Focus Immediately: Before attempting to press Spacebar to start the demo, explicitly click the center of the game window. If the application lacks focus, your inputs will not register, leaving Susie completely defenseless during the first round.
• Do Not Attempt to Dodge During Green SOUL: When Susie's shield is active and anchored, pressing the arrow keys will not move her character model. You must completely shift your mindset from evasion to interception; focus strictly on pointing the axe toward the incoming threat.
• Anticipate Diagonal Blocking: As the difficulty ramps up, projectiles will spawn from the corners. Practice resting your fingers between two directional keys (e.g., Up and Right) simultaneously so you can quickly snap the shield to a diagonal position without hesitation.
• Track the Shell Bounces: When Gerson utilizes his shell-based attacks, do not relax after your first successful block. The shell mechanic dictates that projectiles will ricochet. Keep your eyes on the projectile's trajectory, not just its initial spawn point.
• Manage Your TP Strategically: Since the DEFEND and TP systems are functional in this demo, use rounds with easier patterns to intentionally build up your Tension Points through precise blocking, which provides a critical advantage for managing your overall health pool.
• Adapt to Red SOUL Transitions: If the mechanics force a transition back to the Red SOUL, immediately abandon your stationary blocking mindset. You must instantly revert to traditional free-movement dodging, utilizing the entire battle box to survive.