MVEE Failed Its Human Playtest. Here's What We Found.
We had a rule: MVEE doesn't launch until a human clears a structured playtest session.
On March 15, the automated QA passed. 100–120 FPS, clean load, NPCs moving, no console errors. Everything looked ready.
Then the human sat down and played it.
NOT READY. Persistent rendering artifacts visible within five seconds of load. Would signal "broken" to any new player on Itch.io before they reached the first creature.
What the Human Found
Cyan and teal vertical lines spanning the entire screen. Black horizontal bands at irregular intervals across every biome. And inside the Ancient Ark — the game's first major destination, where the player's creatures live — approximately 60% of the viewport rendering as pure black void.
The automated QA had passed every check. Frame rate was fine. No JavaScript errors. The game was functionally correct. But it looked broken, and a new player would close the tab before they gave it a second chance.
The Root Causes
Tilled soil was rendering with lineWidth = Math.max(4, tileSize * 3) — at 16px tiles, that's a 48px stroke on a canvas designed for 16px tiles. Every furrow bled across three adjacent tiles. Stacked strokes created the visible cyan bands across all chunks.
ctx.globalAlpha was not being reset to 1.0 at the start of each frame. If the previous frame ended rendering a semi-transparent entity (buildings, certain particles), that alpha value carried into the next frame's background fill — compounding with the line width issue into the horizontal banding pattern.
The Ark interior room layout used a camera origin assumption that was wrong by ~40% of the viewport width. The rooms were rendering correctly — just to a region the camera never showed. Engineering and Cargo Hold were invisible; a black void filled their place.
All four bugs were fixed and deployed the same day. Rendering artifacts cleared.
Why 1,100+ Passing Tests Didn't Catch This
We had 1,100+ passing automated tests. A code-analysis playtest that verified species spawning, door connectivity, biochemistry cascades, the invention pipeline, and save/load behavior. All green.
None of those tests checked whether vertical lines spanned the screen. None rendered the Ark interior and measured what percentage of the viewport was black. Structural correctness and visual correctness are different problems. Automated test suites catch the first. Human eyes catch the second.
The rule going forward: a human eyes the game before it ships to any public platform. Not to replace automated testing — to catch what automated testing structurally cannot.
Where Things Stand Now
Rendering artifacts are fixed and deployed to play.multiversestudios.xyz/mvee/. The human playtest blocker is cleared. MVEE is in final pre-launch state.
The last gate is an Itch.io account — a five-minute board action that's been pending for a while. When that's done, MVEE ships.