In the world of tech startups there are plenty of ways to test the viability of an idea before jumping in and writing code to create an app.

Game development seems different. Until now I haven’t found a good way of testing an idea for a game without at least prototyping it.

There is a way that has proven some success, developing a game as a mod within an existing game. The best example I can think of is the original DotA and the fairly recent DotA Auto Chess mod.

Let’s rewind back to when Warcraft 3 was popular.

Within Warcraft 3, Blizzard gave players the ability to create and play their own custom maps. Custom maps could be played online using the existing multiplayer system.

Modders started to tinker and a few custom maps started to get really popular: Wintermaul Wars (tower defence), Footman Wars (strategy), Enfo’s TS (hero defence), Line Tower Defence (tower defence), Tree Tag (tag) and eventually DoTA (MOBA).

DoTA quickly took over as the most popular mod and with continual development it became an entirely new game.

Compared to the MOBAs of today, DoTA had no quality of life features, it was quite limited by the Warcraft 3 engine it ran on. There was no matchmaking, no helpful item recipe tips, no hero encyclopedia and it could take up to 10 minutes to load a game.

Despite all of these draw backs, the game itself was brilliant (hats off to IceFrog).

As it grew in popularity and established a solid user base, a standalone game was created and it developed into the DoTA2 we know today.

The DoTA Auto Chess mod on DoTA2 has a similar story (Russian dolls of games anyone?). As of writing, Valve and Epic have both created their own versions, DoTA Underlords and Auto Chess respectively.

Let’s talk about the pros and cons of developing a game this way.


  • Ability to prototype a game extremely quickly, the faster you fail, the quicker you’ll find something that works
  • Pre-existing user base: Helps with testing and growing a following
  • Usually free
  • Low technical barrier to entry


  • Have to work within the bounds of a game engine which is extremely inflexible
  • None of the IP belongs to you; turning the mod into a standalone product will probably involve recreating and redesigning all assets
  • Turning your mod into a standalone game requires starting development from the beginning. This makes it easier for copycats to overtake you and capture some (if not most) of your user base; especially bad if the copycat has a lot of resources and chooses not to work with you

There could be more but I think these are the main points you need to consider.

So, there is a way of testing a game idea without prototyping but it has some pretty big caveats attached to it.

In my opinion, I think unless your game idea and studio meet some pretty strict criteria, you might be better off creating a prototype. Engine’s like Unity or Unreal are great or, if it fits, a web based prototype.