Introduction

Digital Chocolate is a mobile games publisher committed to delivering top-notch titles to the market, which in return ensures that here at Sumea, Dchoc’s internal development studio in Helsinki (Finland), not a single boring day goes by. Aside from delivering a constant stream of solid titles, we’re also proud to say that our company is spearheading the innovation efforts within the mobile games industry with several un-licensed, outside-of-the-box-thinking game concepts such as Mobile League Sports Network (MLSN) and Johnny Crash Does Texas.

The more recent concept in this family is Tower Bloxx, which received a green light for production a bit over a year ago. Now looking at its market acceptance and its slightly bending industry awards shelf (from IGN to the Meffys to the Mobies), it’s clear that it has become one of the crown jewels of our studio.

In case you haven’t tried it yet (bad, bad you), the game in a nutshell is a mixture of timing-based action and puzzle. To quote some reviewers, it’s like “Tetris meets Sim City.” Your ultimate mission is to create a Megalopolis of millions of people (the Tower Toons) by building skyscrapers where they can live. The better you perform in building the towers, the more Tower Toons will be able to move into your city.

In the one-button action mode, you build a skyscraper by stacking floors on top of each other. You do this by dropping them from a crane. It would be easy except for the fact that it’s windy, so the floors swing a little bit (well, quite a lot once you get really high up there), and it’s crucial to get the timing right.

Tower Toons will be moving in according to how precisely the floors are dropped on top of each other and also by how fast you do it. Drop them too close to the edges of the tower and it might fall down, maybe even bringing some finished floors with it. If you drop floors incorrectly too many times, the construction of the tower will be aborted for safety reasons (even a virtual city can afford only so many engineering screw-ups). To finish a tower, you drop a roof on top of it. Now that the icing is on the cake, it’s time to choose where to place the tower in your city.

This is where the puzzle element kicks in. The city mode challenges you to place the towers in the most optimal way to get the highest population count possible out of the city. There are four tower types that you can choose to build (10, 20, 30, and 40 floors) and for each of them there’s a strict rule where it can be placed. 10-floor towers can be placed anywhere around the city, while the hardest 40-floor towers have to have all the other building types surrounding them in order to be placed. There are also a limited number of slots where you can place towers.

We wish we could share how to come up with nice concepts easily, but in reality there’s no easy way to go about it. In the case of Tower Bloxx, the whole process started in a brainstorming session. The idea originally involved a train, but it evolved into something like a tower during the session itself. From that, a quick mock-up image was made by one of our designers where a hand drops a block to form a pile of blocks.

Excited about this image, we decided to develop a simple throw-away prototype with very simple graphics, which was called “drop the box” (left). By showing it around we noticed that we had to pry the phone away from people after they had started playing, which was a good sign. However, before our product management team would let us go off and build this into a game, they asked us to find a good theme to wrap around it. We brainstormed many theme ideas, and in agreement with our product managers we decided to go for the current theme, which was also the studio’s favorite.

Here at Digital Chocolate a broad handset support is a must (we’re not happy just having our games running at high-end phones, so we always shoot for 100% support), so this is always one goal in our projects. Aside from this, the project had three major goals:

• Create an innovative game that differs from the current market offerings.
• Make the gameplay easy and fun but deep enough to keep the player playing again and again.
• Develop in parallel a 3D version reusing as much as possible from the 2D one.

With these challenges in mind, we set out to solve the four-month puzzle of building Tower Bloxx.