Prototype, Vertical Slice, or MVP: What Your Raise Should Buy

The difference in vertical slice vs prototype vs MVP is what each one proves. A prototype proves the core action is fun. A vertical slice proves the team can deliver final quality on one small piece. An MVP proves real players will keep playing a released game. Your raise should buy the next proof your investors need, not all three.

Why the label matters to your runway

These three terms get used loosely, and that is where budgets go wrong. A founder asks for an MVP, the studio quotes a vertical slice, and the board expects a prototype in six weeks. Everyone is talking about a different build.

Each build costs a different amount and answers a different question. Picking the wrong one means paying for proof nobody asked for, or arriving at a board meeting without the proof they wanted.

The three builds side by side

The table below gives typical ranges. They are rough planning figures and vary a lot by genre and team size.

The key point: they are not three versions of the same thing. Each one is built for a different audience.

The prototype: proof of fun

A prototype is rough on purpose. It has one mechanic, no menus, and placeholder art. Its only job is to tell you whether the core action holds attention.

It is the cheapest proof you can buy and the one most often skipped. Founders who skip it end up testing the core idea inside a full production build, which is the most expensive place to discover it does not work. Our guide on what a game prototype is covers the basics.

The vertical slice: proof of quality

A vertical slice is a thin cut through the whole game at final quality. One level, with real art, real audio, real UI, and the core loop working end to end.

It is the build that persuades people who cannot imagine the finished game from a grey box. That is usually investors and publishers. It is also a strong test of the team, because it shows whether they can actually deliver the quality the pitch promised.

A vertical slice is a sales and diligence tool. It is not a market test, because nobody has downloaded it.

The MVP: proof of retention

An MVP, a minimum viable product, is a real game released to real players, usually in a soft launch in one or two test countries. It has enough content to measure whether people come back.

The proof here is data: D1 and D7 retention, the share of players who return one and seven days after installing. That data is what next-round investors care about most. Our post on what an MVP feature list should cut helps keep it narrow.

Matching the build to the raise

The right build depends on where you are and what the next round needs to see.

1. Pre-seed or angel money: buy a prototype. Prove the fun before spending more.
2. Seed round with a publisher or investor pitch ahead: buy a vertical slice, after a prototype has passed.
3. Seed round aiming for data-driven Series A: buy a prototype, then go straight to an MVP and soft launch.
4. Larger round with a proven concept: plan for an MVP and the first months of live updates.

Notice that the prototype appears in almost every path. It is the cheapest risk check in game development.

Common mix-ups that cost money

A few patterns show up again and again.

• Polishing a prototype. Adding final art before the mechanic is proven wastes art budget on an idea that might change.
• Calling a vertical slice an MVP. A slice has no retention data, so it cannot answer the market question.
• Building an MVP with too much content. The point is the smallest game that can measure retention. More content delays the data.
• Skipping straight to an MVP. If the core action is not fun, the MVP will tell you, but only after months of work.

How to explain the choice to your board

Boards respond well to a simple chain: each build reduces one risk before the next spend. Our post on building a test plan your board can read shows a one-page format.

Name the risk, name the build that tests it, and name the result that would justify the next step. That turns a technical choice into a funding plan.

What we would do

We would almost always start with a prototype, even if the raise is large. Two to six weeks of rough testing is cheap insurance against a much more expensive mistake.

After that, we would ask one question: does the next investor need to see quality or data?

Quality points to a vertical slice. Data points to an MVP and a soft launch. Building both before the next raise is rarely the best use of runway.

The short version

• A prototype proves fun, a vertical slice proves quality, an MVP proves retention.
• Each build is aimed at a different audience and costs a different amount.
• Start with a prototype in almost every case. It is the cheapest risk check.
• Pick a vertical slice if your next audience needs to see quality.
• Pick an MVP and soft launch if your next audience needs to see data.

If you are deciding which build your raise should buy, we can walk through the options with you.

Related reading: What is a vertical slice, 5 signs your game idea is ready for an MVP, Soft launch: how to test before you spend