/ Problem
Sustaining a game you can't really lose
Aqua-Deco is a cozy aquarium-shop sim where the player stocks a store, builds an aquarium attraction, and decorates tanks. The design problem sits underneath the genre: cozy means low stakes, and low stakes risk low investment. The player can botch a photo competition, but they can never be ruined. Meaning the shop never goes broke, and customers will always come. While the pace might slow to a crawl if the player is doing poorly, it's always possible to climb back up. So the central question this design has to answer is the one every cozy game faces: how do you keep a player motivated when they can't actually lose?
/ Approach
One creative act, three payoffs
The design principle the whole game is organized around: arranging your tanks and shelves is a single creative act that pays into three places at once: it attracts customers to the aquarium side, it scores your photo-competition entries, and it delivers the player's own expressive pride in the space. Decoration isn't a side activity that sits next to the game; it is the game, feeding every system that matters.
01 — Progression by Achievement
Creative rank, not money
The loop is decorate → compete → rank up → unlock better decorations → decorate better. In shop sims like TCG Card Shop Simulator, you grind money to unlock better stock. In Aqua-Deco, the progression currency is competition rank. Advanced and exclusive decorations are visible in the online store as a preview but stay locked until the player's photo-competition rank earns them. You advance by making nice things, not by optimizing cash. That's the mechanical expression of "cozy."
02 — The Keystone
The scoring rubric
This is the system the rest of the game leans on, and the hardest one to really define. The working model: every decoration carries tags - color, theme, style, rarity/tier - each with a value, summing to an overall score, with combo multipliers that reward intentional pairings placed in the same tank. On top of that sits the layer that makes it a design problem rather than a math problem: the fish. A fish must first be content in its environment to grant bonus points, and must also match the tank aesthetically for further bonus. That constraint is pressure - it stops the player from just dropping in the highest-value items, because the space has to cohere around its inhabitants. The lineage is Zoo Tycoon's enclosure design, where the right rocks, plants, and toys keep an animal happy, repurposed for aquascaping.
03 — TWO INCOMES, NO BANKRUPCY
One loop, no terminal edge
Income comes from two sides the player chooses between aesthetically: lean into retail sales, lean into aquarium attraction, or balance them, it's purely a taste decision with no mechanical penalty either way. Both avenues just feed money into the one loop that matters: restocking, employees, expansions, and bills. Money has weight (it gates space and upkeep) but no terminal edge - fail hard and ticket sales still trickle in, but slow significantly. The real stakes live entirely in the competitions; the day-to-day is a safe harbor.
The Open Problem
The photo competition
Let's just state it plainly: the competition is simultaneously the pride payoff, the progression gate, and the justification for the entire shop-and-aquarium apparatus. It's also the least-built, most intricate system in the design. The whole motivation structure weighs pretty heavily on it. Scoring will be relative (judged within your tier, with a clear path upward) specifically so difficulty rises without tipping into frustration. Solving this rubric so it feels legible, fair, and creatively expressive is the central design challenge of the project that is currently left unsolved.
/ Implementation
Current state
The retail loop is the part under active development: customers spawn on a timer, move to observation points or shopping points, and the player restocks shelves and checks out customers. Customer AI currently runs on a rudimentary motivation tag system (Retail / Aquarium / Both) that's randomly assigned upon spawn. As the project progresses I'd like this to evolve into including spawn-time shopping lists that drive customers shelf-to-shelf. The photo competition, photo mode, and the tag-based scoring rubric are also designed, but not yet built.
Fig. 1: Retail loop — in development
Fig. 2: Tank decoration — the one creative act
Fig. 3: Scoring rubric — designed-not-built
(Media slots to fill as the prototype develops.)
/ Outcome
What the design is built to produce
The intended result of the decoration pillar is that a player decorating purely for their own pleasure is automatically progressing. This is the same arrangement that satisfies them as well as the one attracting customers and scoring rank. Nothing asks the player to grind against their own enjoyment. Whether that holds up is what the prototype exists to find out; this is design reasoning ahead of implementation, documented before the build can muddy it.
Differentiator
Progression gated by creative achievement rather than money — the carrot of visible, but locked, decorations pulling the player toward competitions, not toward a bigger bank balance.
Authorship
Solo design and development: every system here is mine, which is also why scope discipline matters: I built the straightforward retail loop first and deliberately deferred the photo competition until it could get the design time its intricacy demands.
Status
Prototype. Everything above is subject to change; the coziness itself is an intended quality the development is working toward, not a solved one.
Progress by making, not grinding
Creative rank, not cash, gates the good decorations.
One act, three payoffs
Arrangement drives attraction, score, and player pride together.
Coherence over accumulation
The fish layer rewards spaces that cohere, not item-dumping.
Honest scope
Straightforward retail loop built first; the hard keystone named, not faked.