For many games, the basic energy mechanic is both the lifeblood and revenue stream for the game. To better understand the energy mechanic I like to use Super Mario Bros as the example. During a single game session you get x number of lives. As you go through the game and loose to the various challenge elements, you slowly loose your in game lives. Once all of your lives are up, the game is over.
How to add an Energy Mechanic
Many apps today employ the same energy mechanic but in different forms. Games may use terms that make sense to their game such as Health or Stamina or Gas, etc… The basic concept is all the same. You start with x amount of healthy or stamina. Performing an action takes y amount of health or stamina. Once you are all out you have to either start over or at a period of time to play again.
Another game example from recent years is the game Hill Climb. You start with x amount of gas, as each second ticks by in the game your gas tank starts to drain. Once you run out of gas the game is ended and you have to start over. Each time you play you earn coins which allows you buy better and faster cars allowing you go further each game.
The energy mechanic is so important because it provides a way to gate your game behind either time, skill or in game progress. In the Super Mario Bros example it was gated behind skill. If you didn’t have much skill your lives would end quickly. As you gained more skill your lives lasted longer and you were able to get farther in game. In the Hill Climb example it was gated behind an in game buildable. You start off with a very low level car that is not able to go far and thus you run out of gas quickly. As you played you collected coins and were able to build a faster car allowing your gasoline to last longer.
Energy and Game Economies
Another valuable aspect of the energy mechanic is that is offers game designers an additional revenue stream. As long as this is not abused, this can be a very lucrative channel for games. Imagine playing a game and being just within reach of your goal only to have your energy run out. It's a huge disappointment. If you offer your users the chance to “continue with extra energy” for a small fee, many users will take it.
In addition, an energy mechanic allows you a way to set an economy within your game and place value on a certain action. This is very useful if you game follows the city builder style games that allow users to build different types of objects within their game board. They can build a lower level item or perform a lower level task for a small amount of energy, or they can build a higher level item or perform a higher level task for a large amount of energy.
Pitfalls of an Energy Mechanic
Spending too fast. Pay very close attention to the energy spend during the first several game sessions for new users. It is critical to the success of your game that new users can’t spend all of their energy in too fast a manner. Aim for a first play session that allows for ample time to get into the game and explore all the basic elements. Don’t let your users spend all of their energy too fast or else they will not find the game fun.
Not enough for higher level user. Similar to the new user problem of spending energy too fast, you need to also watch out for your higher level users. Make sure that they are able to maintain or store enough energy to perform several tasks at their higher levels. Many games see drop offs at higher levels because their users are only able to perform one or two tasks before running out of energy. A game that only allows a couple of actions, is not very fun.
Exploits. Since the energy mechanic becomes your life blood, pay very close attention to exploits within your game. Although code bugs and hacks can cause these, they are more often found in poorly designed features. For example is you allow users to send energy back and forth to each other as a in game feature, add in daily caps otherwise users will create hundreds of fake accounts and use them to send energy between them all day.
