Merlin vs Alfonso

A note on how this review was built: the developer has not published a licence for their own code (no LICENSE file, no statement in the repository beyond crediting the MIT-licensed ZzFXM and ZzFX audio libraries it uses). It's published here credited to Grav by name with a link to the developer's own GitHub repository, and with a same-day takedown offer standing if they'd prefer it not be hosted here.

King Alfonso X of Castile really did commission the Libro de los juegos, a 13th-century manuscript documenting the rules of games played at his court, including a chess-like game called Ajedrez. Merlin vs Alfonso takes that specific historical detail and builds a real puzzle mechanic on top of it: enemy pieces on each isometric level move according to rules pulled directly from that text, while you, playing as a fictionalised Merlin, drag gold-coloured objects with telekinesis and walk toward a goal tile, planning routes that account for how each chess-descended enemy will respond. It's a genuinely clever fusion of a real historical curiosity and a Monument-Valley-style spatial puzzle, and the reception reflects that: js13kgames.com's own archived 2023 results place it 2nd out of the entire competition field, with individual top-5 finishes in four separate judged categories including a 3rd-place finish for Innovation specifically.

An unusually well-documented mobile story, straight from the developer

This is the section where this review leans most heavily on a source better than its own testing: the developer's direct, public replies to the 28 comments this entry received. That's worth taking seriously as evidence, because it's the developer confirming or apologising for specific reports rather than a reviewer guessing. Ben Fox wrote that he "had some difficulty on Mobile initially as it wasn't clear which orientation I should use, and in Portrait mode the click-to-mo[ve]..." was inconsistent; the developer, posting as Grav, replied: "apologies for the experience on mobile but I'm happy it worked on desktop." Separately, John Edvard reported a rough experience "on iphone mini," and Grav replied: "I'm sorry about your experience on iphone mini, I did test on regular iphone, but not on the mini. Was it in landscape mode?" Both exchanges describe the same category of problem — screen orientation and device-specific inconsistency — from two independent players, neither disputed by the person who'd have every reason to push back if the reports were wrong.

That's not the whole picture, though, and it would be unfair to lead only with the criticism: Magnus Lindh, in a separate comment, called it "beautiful" and specifically noted it was "playable even on a touch device." Reading both sets of comments together, the fairest summary is that touch input fundamentally works, but the experience is meaningfully less polished on mobile than on desktop, particularly around orientation handling — exactly the kind of nuanced, real finding that first-party developer replies can surface better than an automated test in most cases.

This review's own testing adds one clean, positive data point to that picture: every dialog and menu interaction — dismissing tutorial text boxes, advancing between instruction screens — was tested with real touchscreen taps and worked correctly and consistently every time. What this testing could not conclusively confirm, given the time available, was the walk-to-point and drag-to-move mechanics specifically, which is exactly the layer the community reports above describe as the rough one. That alignment between an inconclusive automated test and a developer-acknowledged rough edge is itself a useful signal, even without a definitive first-hand result.

Presentation

The isometric SVG art is the easiest thing to say something confident about, because ten separate judges reached for the same comparison independently: Monument Valley. Confirmed directly in testing, Merlin's castle renders in flat, vivid jewel tones with genuine depth cues — arrows and highlighted objects use a distinct cyan that reads clearly against the purple stonework — and the developer confirmed in the comments that the entire scene, characters included, is built from SVG paths rather than raster art or canvas drawing, an unusual and effective choice for a puzzle game built to a strict size budget.

Final verdict

Merlin vs Alfonso earns its 2nd-place finish honestly: a genuinely original mechanic grounded in real medieval history, presented in a style distinctive enough that a room full of competition judges named the same visual influence independently. What keeps this at a 7.5 rather than higher is the mobile experience specifically — not because it doesn't work, but because the developer's own direct replies to real players describe orientation confusion and device-specific inconsistency that this review has no reason to doubt. Play it, but play it on a desktop first if you have the option, and don't be surprised if a phone needs a rotation or two to feel right.