Making a cross-platform game in two weeks

In today’s post I would like to share with you my experience working on my first cross-platform game. Although it is intended to be available for Windows Phone, iOS and Android, currently I’m focused on the Windows Phone version.

The game is called Muster my Monsters (MmM). It is a two-player fighting monsters action game. It is a casual game, so game mechanics need to be simple and art appealing to most of people. Here you have a gameplay video.

Problem statement

The problem statement for MmM has some unusual restrictions due to unusual circumstances. First, I wanted to submit it to the first CELL APP Awards. As you can see at the official website, the deadline has been extended, but the original deadline was April 30. By the way, you can help Muster my Monsters win the contest by voting for it here 😀

I also needed a game that could start simple enough to be ready in two weeks but with potential to grow naturally, in case I want to keep working on it after the contest.

So, the problem statement is:

I need to design and develop a cross-platform game using CELL·SDK in two weeks. It needs to be simple but with potential to grow and appealing for casual audience. No level design involved.

Why CELL·SDK? Well, because it is mandatory to participate to the contest 😉 But also because it is a promising cross-platform development tool. In this post you have more details about my reasoning around cross-platform development on mobile devices.

Why only two weeks? Well, due to some personal and technical problems, I started to work on this game only two weeks before the contest’s deadline. That’s why I needed a simple game without level design involved. Level design and balance is very time consuming.

Game Design

The core gameplay of Muster my Monsters is rock-paper-scissors. Yes, it is essentially a rock-paper-scissors game with a nice dress 🙂 However, upon this extremely simple game mechanic you can build up a very solid video-game.

The available actions in Muster my Monsters are: Attack, Dodge and Mock.

  • Attack wins Mock
  • Mock wins Dodge
  • Dodge wins Attack

The current version of Muster my Monsters has two game modes:

  • Single Player. You play against the COM. Currently it is like a slot machine game because the COM selects the action randomly.
  • Two Players. This is the fun part 🙂 Here I take advantage of the intrinsic gameplay richness of rock-paper-scissors. I have put my main effort on calibrating correctly the timings and phases of every round and match of the game to make the players feel the rock-paper-scissors tension.

But MmM is also a fighting game, so I can naturally add game modes such as: tournament, arcade, survival, time attack…

MmM is also about monsters. Do you like collecting monsters? 😀 Both casual and hardcore players love to collect things. But collecting monsters is the best! Moreover, this is an interesting feature for monetization.

Maybe I could break a little bit the rock-paper-scissors balance. What about a very strong monster that gets some advantage after winning a throw using the Attack action? Would that player use Attack at first round? Or would avoid it because it’s too obvious? Nice dilemma 🙂

So, as you can see, this little game may easily grow up.


CELL·SDK is a promising cross-platform development tool that supports iOS, Android and Windows Phone with the same code base. They are still working on it, but it already offers some very interesting features such as a modern physics engine, support for sprite based animations, key-frame based animations, integration of various advertising platforms, analytics…

The main drawback is the cost. CELL·SDK is built upon MonoTouch and Mono for Android, so you will need the corresponding licenses to publish games and apps for iOS and Android, apart from the CELL·SDK license.


For all the art of Muster my Monsters I talked with Javi Sanz, from Ravalmatic. Menu screens, game HUD, character design, sprite animations, background… Everything.

It is amazing how he could manage to do everything taking into account that I first talked to him about the game two weeks before the deadline. Great work Javi!! Thanks!! 😀

Music & SFX

The music and, specially, the SFX are very important for this game. The background music builds tension and the SFX help the player to understand the action and being aware of the current game state.

It is important that the payer can easily know how many rounds has win/loose so far and the number of matches played so far. But the most important thing is that the player could internalize the timings and phases of the game, as well as the history of actions delivered both by himself and the opponent. And for achieving this, the SFX are as important as the visuals. The sequences of sounds are easily retained unconsciously by players.


The most important conclusion I get from this stressful experience is that it is possible to create a playable and fun game within two weeks. It still needs some polish, but the main part is already developed.

It also has allowed me to introduce myself to the Windows Phone platform. Microsoft technologies are really great: C#, XNA, Silverlight, etc. All of them are modern and robust tools that make your life easier as a developer. In the future I will see if it happens to be the same with the Marketplace and the publication and distribution phase.

So, let me remember you again that you can help Muster my Monsters win the first CELL APP Awards voting for it here. Wish me luck! Thanks! 😀

This post is part of iDevBlogADay, a group of indie iOS development blogs. You can keep up with iDevBlogADay through the web siteRSS feed, or Twitter.

5 thoughts on “Making a cross-platform game in two weeks

  1. I would love to play this on my windows phone.. seems like a good banter game to play with your mates in your break.
    great idea!

  2. Pingback: Making a cross-platform game in two weeks [Toni Sala] (iDevBlogADay) |

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