Energy seems to be hated by designers and players alike, so why does it endure as the hallmark of casual F2P games? The fact is that whilst it’s a crude mechanic, it’s also an efficient one, delivering several functions in one easily implementable feature.

This isn’t a defence of energy systems – I’ll follow up with a post on ways of replacing them – but without something fulfilling these roles then it’s unlikely you’ll make a very good game. I’ll talk about energy and timers fairly interchangeably here as they are both pacing systems that function remarkably similarly.

The four main reasons that mobile designers use energy systems are:

1. Habituation
2. Content pacing
3. Monetization
4. Strategic choices

1. Habituation
The primary reason that designers use energy systems is to encourage players to play as long and as frequently as they would like. The amount of energy gives an easy way to fix the…