Plants Vs Zombies: Introduction to perfection

The formula for the perfect game may be an area of hot discussion, but most would argue that games that are easy to get into and difficult to put down goes along the right lines. Players' early experience of a game is critical: this is the period in which they're making up their minds whether to devote more time, and often money, to the rest of it. 

So how do we make games with a polished early experience? Let's take some lessons from a game which I think does it incredibly well, PopCap's Plants Vs Zombies. 

There are many points during the opening of a game at which a new player may decide to stop playing. This process is often visualised as a funnel: you have many potential players interested in your game (the wide part of the funnel), but each progressive step has the potential to cause players to leave. The hope is, of course, that enough players emerge at the narrow end of the funnel to make the game a success.

So what are these steps in the funnel, and what does PVZ do to ensure that as many players as possible squeeze through funnel? Let’s divide the funnel into five key sections, and look at the best practices in each.

1 Pre-game

This step might include a game intro video and character creation, but PVZ doesn't. The game loads and you just have to enter your name. You wanted gameplay, you've got it; PopCap wants you to get to the action right away.

2 Menus

These can be a real barrier to gameplay for several reasons. First, the more menus you offer, the more the user may explore, each one delaying time taken to get to the game. Secondly, the more choice you offer, the more you may confuse the player. Some players may feel confused by some of the terms used or be scared of making a wrong choice. Reducing the number of menus, especially in "casual" games, lessens the possibility of players leaving.

PVZ is masterful here, offering only one game mode and immediately beginning. There is no difficulty level, no pop-ups to dispatch. All unnecessary friction has been eliminated.

What’s interesting at this point is the delay between selecting the option to play and the time taken to actually start the game - 12 seconds. The first seven seconds of that is displaying 'PopCap Presents', then a further five-second action-packed gameplay movie. Other studios put their logos and intro movies up front, causing frustration for some players, because they’re here to play the game. PopCap gives you the game, then shows the gameplay movies. More satisfying? I think so. 

3 Tutorials

Explaining a game’s rules is crucial, but it’s an art to do it in a best-practice way. The easiest option would be to explain every mechanic and HUD element by providing wall-of-text instructions, but few players will read it. PVZ explains only the core game features – plants and sun – and that’s it. It encourages the player to explore and learn by doing, which is much more satisfying than learning by being told. PVZ also creates a safe environment in which to learn as it’s impossible to fail the first level. Everyone’s a winner. 

4 Player engagement

Now that we have the player’s attention, how do we keep it? PVZ employs several strategies to keep players keen by introducing new plants, zombies, mini-games, and other features. What’s clever is how it does this of course.

At the end of each of the first eight levels the game awards the player with a new plant. This alone will encourages them to try it out on the next level, but the game also employs other tactics. For example, it’s very difficult to exit the game; when you complete an Adventure mode level, the game doesn't offer the option to continue to the next level or quit. It simply starts the next level. Combine this with the curiosity to try out a new plant and chances are that you'll continue. 

This pattern repeats until level eight - by now, the you've has spent at least 30 minutes with the game, and a very precisely designed 30 minutes at that. If this were a demo, chances of a sale are looking good. 

5 Encouraging return

At some point, players will stop playing, but how do you bring them back again? The author Haruki Murakami says, "When writing a novel, I stop every day right at the point where I feel I can write more. Do that, and the next day’s work goes surprisingly smoothly." PVZ uses this exact philosophy. Most players would typically end a game session at the end of a level, but by giving the player a new plant at this exact point, even if they do leave, an incentive has been created to come back. 

PvZ is a masterclass in early experience design. We’ve only touched on a handful of the techniques PopCap uses to deliver an accessible game that encourages long-term play. 

What’s amazingly clever about PVZ is that it works for both core and casual users. PopCap says that its sales are an equal 50/50 split between core gamers and broader audiences, and it’s easy to see why; casual users feel supported whilst core users can issue themselves challenges or try out new strategies.

This level of polish doesn’t come easy, of course. It requires refinement, and lots of it. PopCap spent three years developing PVZ, prototyped early and playtested often. Casual fun requires serious effort.