The sword draw (batdo, 발도) and the sword sheath (napdo, 납도) as the two poles of a combat loop is a design idea with specific cultural grounding. The Japanese iaijutsu tradition — the art of drawing the sword as a single, complete attacking motion — treats the draw itself as the decisive action rather than a sustained exchange. SURA: Shattered Star from Korean studio HanRyang Studio extends this concept into a system where the draw leaves marks, and the sheath detonates them: the two actions are not standalone attacks but complementary phases of a single strategic sequence.
The game launches free on Steam July 31 as the fourth Jungle Game Lab project covered this month (alongside No Results Found, ON&OFF, and A.D.D.), and is explicitly framed as a proof-of-concept: approximately two months of development, focused on validating the core gameplay mechanic rather than delivering a complete commercial product. The free distribution is the correct decision for that scope and intent — the team wants players to experience and respond to the combat system, not to evaluate a finished game.
The Mark System
The batdo/napdo combat loop is most clearly understood as a two-phase sequential mechanic rather than two independent actions. The draw phase (batdo) applies marks to enemies hit during the attack — these marks are the accumulated potential of the encounter, the sum of damage not yet delivered. The sheath phase (napdo) detonates all accumulated marks simultaneously, turning the potential into actual damage across every marked enemy at once.
This creates a combat structure organized around restraint and detonation. The player who draws and immediately sheaths hits one enemy once and detonates a single mark — minimum value from the system. The player who draws, moves rapidly through a group of enemies while the draw attack applies marks to each, and then sheaths at the moment of maximum accumulation — hits every marked enemy with the simultaneous detonation. The gap between these two uses of the same mechanic is the game’s skill ceiling.
The timing and sequencing decisions this creates are specific: when have I marked enough enemies to justify detonating? Is there a better position to trigger the detonation from, where the chain kills will create space for the next sequence? Which enemies should I prioritize marking, given that the detonation will eliminate all marked targets simultaneously?
The developer’s description captures the loop’s rhythm precisely: “The moment of drawing is when the execution begins; the moment of sheathing is the preparation time for the next strike.” This framing emphasizes that both phases are active strategic actions — neither is neutral movement between attacks. The draw is the setup; the sheath is the payoff; the player’s skill expression is in the quality of the setup that the payoff resolves.
The Space Opera Noir Setting
A retired mercenary swordsman who lost everything to a megacorporation, seeking revenge through the layers of a massive orbital station while uncovering concealed truths about what was done — this is a specific genre hybrid that SURA executes through pixel art that combines science fiction and noir aesthetics.
The noir register in science fiction tends toward cynicism about institutional power: the corporation that did the harm, the system that ignored it, the individual who suffered and now acts outside the system to address what the system won’t. Sura’s revenge premise is this template, and the layered station environment (research facilities, industrial zones, military areas) provides the escalating institutional depth that the template requires. The deeper into the station, the closer to the truth, the higher the institutional stakes of what’s being concealed.
The ninja, pirate, and criminal organization elements added to the SF noir aesthetic give SURA‘s world a pulp texture that distinguishes it from more severe science fiction presentations. Pixel art with this kind of genre layering tends to feel like it’s in conversation with specific genre traditions rather than trying to reproduce cinematic realism — which is appropriate for a proof-of-concept that’s primarily demonstrating a combat system. The world doesn’t need to be fully realized for the movement and combat to show their potential.
The Jungle Game Lab POC Format
HanRyang Studio’s transparency about the project’s nature — approximately two months of development, explicitly a proof-of-concept for the core gameplay, focused on validating the mechanic rather than delivering complete content — is a different kind of release honesty than the “Early Access with complete beginning-to-end experience” that Spirit Route‘s Curious Forge described this week.
Both are legitimate models. Spirit Route entered Early Access with a complete core game ready for expansion. SURA: Shattered Star is releasing a focused demonstration of a single mechanical idea to gather player feedback before deciding what a fuller development would look like.
The development team’s stated goal — “we hope many users will play freely and leave feedback” — is the explicit statement of what this release is for. The game is seeking player validation of the batdo/napdo mark system before committing to the full development investment that a complete action platformer would require. Free distribution maximizes the feedback pool without asking players to commit financially to something explicitly framed as a concept demonstration.
This makes SURA: Shattered Star appropriately evaluated differently from a completed commercial release. The question isn’t whether it’s a complete game (it’s not, and doesn’t claim to be). The question is whether the core mechanic — the batdo/napdo mark loop with aerial maneuvering and chain kills — delivers enough of the stylish action feel that HanRyang Studio is aiming for to justify continued development.
The HanRyang Studio Design Philosophy
“Easy to learn but deeper fun as you become more skilled” is the design aspiration that every stylish action game pursues and that relatively few achieve. The accessible version of the batdo/napdo system (draw, move, sheath) is immediately understandable; the skilled version (mark multiple enemies optimally, time detonation for maximum chain kill potential, maintain aerial mobility throughout) is a genuinely higher ceiling than the basic understanding implies.
This gap — the distance between first-playthrough competence and skilled mastery — is what sustains stylish action game communities. Devil May Cry‘s style rating system, Bayonetta‘s witch time, Metal Gear Rising‘s parry system all have accessible surface-level engagement and substantially deeper skilled engagement. Whether SURA‘s batdo/napdo loop creates a comparable gap between beginner and skilled play is the question that the proof-of-concept is designed to answer through player feedback.
Who This Is For
Strong fit for: stylish action game enthusiasts who want to try a novel mechanic built around draw-and-sheath sequential combat; iaijutsu and Japanese sword-drawing aesthetic fans who want to see the concept applied in a space opera context; players interested in evaluating a concept-stage game and providing meaningful development feedback; Jungle Game Lab followers completing the set of four July releases; Korean indie game supporters; players who want to try a free action platformer with a specific mechanical identity.
Cautious fit for: players who want complete game experiences rather than proof-of-concept demonstrations; action game enthusiasts who specifically need complete content scope to evaluate a game’s appeal; players who prefer evaluating polished finished products rather than concept-stage work.
Less ideal for: players who dislike side-scrolling action platformers regardless of combat mechanic; anyone seeking narrative depth at this stage; players wanting multiplayer options.
What to Watch For
The proof-of-concept framing makes the post-launch feedback the most important outcome of this release. Whether players respond to the batdo/napdo mark system as genuinely novel and satisfying — or whether they find it interesting in concept but not yet compelling in execution — will determine the direction of HanRyang Studio’s subsequent development.
The aerial maneuvering component specifically will be a key evaluation point. Stylish action games live on movement quality; the feeling of moving through space while setting up mark detonations needs to feel fluid and expressive rather than mechanical. If the aerial maneuvering creates the spatial freedom that makes the mark setup feel like active choreography, the system has the feel that justifies fuller development.
The Takeaway
SURA: Shattered Star is HanRyang Studio’s focused demonstration of a specific combat idea — the batdo/napdo mark loop where drawing applies potential and sheathing converts it — wrapped in a space opera noir pixel art setting with a revenge narrative about institutional corporate harm. It’s two months of work on a concept, released free to find out if the concept resonates.
The Jungle Game Lab July release cluster — No Results Found, ON&OFF, A.D.D., and now SURA — has collectively demonstrated a program producing developers who take their experimental premises seriously enough to release them publicly rather than treating them as academic exercises. Each game is genuinely distinct; each is making a specific design argument through its mechanics; all four are free on July 31.
The sword is drawn. The marks are on the enemies. The sheath returns it to position. And somewhere in the gap between mark application and mark detonation — in the space between draw and return — is the combat system HanRyang Studio wants players to help them understand.
July 31. Free. The concept needs your feedback.
‘ 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 |
