August 14 is Korea’s Liberation Day — the anniversary of the end of Japanese colonial rule in 1945. Two games chose this date for their Steam release: The Newspapers of the Day, a colonial-era press censorship simulation that spent months documenting what that period actually felt like, and SURA: Shattered Star, a stylish action platformer about a retired mercenary swordsman taking revenge on a megacorporation in a cyberpunk space opera setting.
The two releases share a date and nothing else in terms of subject matter. But both are Jungle Game Lab productions, both are free, and both are making a specific creative statement through the date they chose to launch.
This coverage previewed SURA: Shattered Star in late July when its July 31 release date was still current. The game has now launched, and the POC it was framed as — approximately two months of Jungle Game Lab development to validate a core gameplay concept — is available for anyone to evaluate.
The Batdo/Napdo System in Play
The core mechanic is elegant in description and demands precision in execution. Drawing the sword (batdo, 발도) while moving through enemies applies marks to each target the attack connects with. Sheathing the sword (napdo, 납도) detonates all accumulated marks simultaneously — every marked enemy takes damage at once, creating the chain kill that is the game’s primary satisfaction delivery mechanism.
The strategic question this creates is specifically: when do I sheath? A player who marks one enemy and immediately sheaths gets one detonation. A player who marks five enemies — moving through them, managing the timing — and then sheaths gets five simultaneous detonations with whatever chain effects the accumulated marks produce. The discipline to hold the sheath until maximum marks are accumulated is the skill the game is teaching.
The developer’s description of the two states captures the intended rhythm: “The moment of drawing is when the execution begins; the moment of sheathing is the preparation time for the next strike.” This is accurate as a design statement. The draw is commitment; the sheath is calculation. Between them, the player is moving through the enemy group deciding where to be when the detonation happens.
The aerial maneuvering extends this into three dimensions. Marks can be applied from aerial positions, and the positioning of the player during the sheath determines the spatial aftermath of the detonation — where Sura lands, what enemies are in reach for the next draw, how the field looks after the simultaneous kills. The combo chain that a skilled player builds across multiple batdo/napdo cycles is the game’s highest expression of its system.
The Difficulty of the Mechanic
What the preview discussion of the POC framing didn’t address as specifically as it should: the batdo/napdo system has a learning curve that the ~2-month development timeline shows around the edges. The game’s combat is satisfying when the mark accumulation and detonation are going as planned. When they’re not — when marks are applied to fewer enemies than expected, or when the sheath timing doesn’t produce the chain kill the player was setting up — the feedback about why the sequence failed is not always immediately clear.
This is the specific design challenge that POC projects face: the core concept can be valid while the communication of that concept in the moment-to-moment of play is still being refined. The batdo/napdo system is a valid and interesting combat mechanic. Whether each individual sequence communicates clearly why it succeeded or failed is the question that the POC’s limited development scope hasn’t fully resolved.
The boss fights are where this matters most. Each boss has distinct attack patterns that require reading and responding to, and the batdo/napdo system’s application to boss encounters is the tightest test of the mechanic: you need to mark the boss during windows, position for the detonation, and manage the boss’s response patterns simultaneously. This is a genuinely demanding combination that will sort players who have internalized the system from those still learning it.
The Space Opera Noir Setting
The narrative frame — retired mercenary swordsman Sura, everything lost to a megacorporation, giant orbital station, forbidden experiments hidden in research facilities — is cyberpunk noir executed in pixel art. The SF and noir visual combination produces the specific aesthetic of a world where grim institutional corruption and physical danger coexist with the specific beauty of space-lit orbital architecture.
The enemies who populate the station — ninjas, pirates, criminal organizations alongside the corporate security forces — give the world tonal variety that pure corporate dystopia sometimes lacks. A megacorporation that employs ninja proxies alongside standard security forces is a megacorporation that’s been around long enough to contract out to whoever gets results, which is exactly the institutional cynicism the setting is depicting.
The narrative investigation structure — moving through research facilities, industrial zones, and military areas toward the truth the corporation has been concealing — provides directional purpose for the action without requiring extensive cutscene time to establish. The pixel art visual register communicates the SF noir atmosphere efficiently, which is appropriate for a POC whose priority is demonstrating the combat system rather than telling a complete story.
The Jungle Game Lab July-August Cluster
SURA: Shattered Star completes the Jungle Game Lab Cohort 5 cluster that has released across July and August: No Results Found (internet cult investigation), ON&OFF (circuit-design deckbuilding), A.D.D. (Backrooms bureaucracy), Wave of Signatures: Blue Sign (maritime insurance underwriting), UNLOAD (bullets-as-health boss rush), Dear Magical Girls (magical girl burnout barrier defense), and now SURA.
Each of these games identified a specific design premise and built a focused proof of concept around it. SURA‘s premise — a sword combat system organized around the draw-mark-sheath detonation cycle — is among the most mechanically specific of the group. The game is asking a single design question: does the batdo/napdo mark system create satisfying stylish action? The development team wants the answer from players who try it.
Who This Is For
Strong fit for: stylish action game enthusiasts who want a Korean-developed sword combat system built around the iaijutsu draw-and-sheath concept; players who enjoy the satisfaction of chain kills executed through proper mark accumulation; SF noir aesthetic fans who want the visual register in a 2D pixel art platformer; Jungle Game Lab followers completing the cohort; Liberation Day players looking for something distinctly Korean that isn’t about the colonial period specifically.
Cautious fit for: players who want a complete narrative alongside the combat system rather than POC-level story context; anyone who finds the mark accumulation system’s communication of failure unclear and needs better feedback to understand what went wrong; players who want the game’s systems fully polished before engaging.
Less ideal for: players who dislike side-scrolling action; anyone wanting cooperative options; players seeking the level of content scope that a full commercial release provides rather than a POC.
The Takeaway
SURA: Shattered Star is HanRyang Studio’s proof of concept for a combat mechanic that is genuinely interesting: the batdo/napdo mark system where drawing applies and sheathing detonates, where the timing of the sheath and the positioning during the draw combine to create chain kills that reward spatial planning and combat discipline. The ~2-month development scope shows in the rougher edges of moment-to-moment feedback, but the core concept is valid and the best sequences — when mark accumulation and detonation go exactly as intended — produce the stylish action satisfaction the studio is building toward.
Free on Steam, five-language support, Liberation Day launch alongside The Newspapers of the Day. Two very different games, one shared date.
The sword is drawn. The marks are on the enemies. The corporation that took everything is ahead. And when the sheath completes, the question this project was built to answer gets its first real player responses.
‘ Information regarding ‘SURA: Shattered Star’
| item | detail |
|---|---|
| Developer | HanRyang Studio (South Korea) |
| Publisher | Jungle Game Lab (Krafton Jungle Program) |
| Genre | 2D Side-scrolling Action Platformer / Space Opera |
| Release platform | PC (Steam, Windows) |
| Release date | July 31, 2026 |
| price | Free to Play |
| Supported languages | Korean, English, Japanese, Simplified/Traditional Chinese (5 languages) |
| core system | Draw/sheath-based combat, Mark accumulation/simultaneous activation, consecutive kills, aerial maneuvers |
| Project nature | Krafton Jungle Game Lab Final Project (POC) developed over approximately 2 months |
| Steam Page | Shortcut |
