Introduction
Over the past few years teaching Game and Simulation Programming at DeVry University, I've noticed a handful of design mistakes that entry-level students often make. That's fine - putting together a solid design for a game is difficult, and requires experience, deep critical thought, and extensive testing (among other things).

In this article, I've compiled my three favorite mistakes. The first is the impulse many students feel to cram as many genres as possible into a game. The second is the need to make everything in a game environment into a weapon. The third is a disproportionate focus on story. These are my favorite mistakes because they betray a certain innocence and excitement about game design that is just so darn cute!

The Cross-Genre Extravaganza
How many genres are enough for one game? The simple answer is it depends on the game, but I'd venture a guess that two is fine, and three may be OK as well, provided you know what you're doing. Like a great chef, you have to know what ingredients are appropriate for a particular dish.

Think about each genre as a spice. Some spices go well together (like basil and oregano), but others don't (like garlic and cinnamon). Furthermore, the spices you choose from depend very much on what kind of dish you're cooking. If you just slam every spice at your disposal into a pot, your final meal won't taste right.

For example, it is fine to add action elements to a puzzle game, but adding puzzle elements to an action game can be dicey. Why? Because puzzle gamers expect their challenges might be timed - that's an acceptable addition; it enhances the fun. But action gamers expect their games to be fast-paced, and the wrong kind of puzzle elements can bring any shooter or arcade game to a grinding halt. Imagine having to solve a Rubik's cube in the middle of an Unreal Tournament battle.

Also, players often enjoy only certain genres. A real-time strategy gamer may not like playing first-person shooters, and vice-versa. So an RTS / FPS hybrid runs the risk of alienating both fans of each respective genre. "The Cross-Genre Extravaganza" is a narrow strait to navigate - it takes a solid understanding of genres to know where they overlap and by how much.

You Can Use Anything as a Weapon
Wow, sounds great! Can I kill enemies with Jell-O? What about hairspray?

As silly as those questions might sound, they get to the heart of why this idea is too lofty for game development. If you tell your players that they can use anything as a weapon, that means they'll try and use everything as a weapon, and most likely end up disappointed. The spirit of the idea is one of true physical realism - something that has yet to be accomplished in game design. It's a worthy goal for all game designers, but the simple fact of the matter is, for reasons both technological and monetary, we're not there yet.

Let's imagine for a moment that we're going to implement such a system in an action-adventure game. Every item that could potentially be used in combat has to deal damage, and the amount of damage an item can cause is calculated based on a value stored in its properties. For every item in the game, that number has to be decided upon and rigorously tested. Every broom, office chair, vase, and milk bottle in your game needs to know how many points of damage it can cause an enemy. That could become quite a tall order for your development team to fill.

What about mounting the object to the player so he or she can wield it? What spot on the item does the player grasp? This problem is usually solved with invisible mount points on both the object model and the player character model that work like positive and negative magnets. Again, for each item in the game, someone will have to manually decide upon a mount point. If that doesn't sound like a problem yet, then consider the different ways you would hold the following objects as weapons - a kitchen knife, a baseball bat, a steel folding chair, a 24-inch television set, and a length of chain. Some of these items have one mount point, others have two. The posture of a person wielding each item also varies dramatically, thus adding to the amount of animations needed for each character model. And with the television set, we see how the weight of the item might come into play, adding even more complexity to the design process - after all, how many times a minute can you swing a television set as opposed to a kitchen knife?

The point is, "You Can Use Anything as a Weapon" is one of those ideas that looks great on paper, but is as of now an unrealistic goal.

It's Based on a Story
So many first year students confuse storytelling with gameplay. It's an understandable mistake, especially when you consider how epic computer and video games have become in the last few generations. Look at the kinds of advertisements the industry puts out to promote its games - overwhelmingly they focus on characters, situations, and stories to sell the product, as opposed to specific gameplay elements. To confuse the issue even more, one need only to look at the library of games for the Wii based on third party IP's to see this story obsession in action: The Ant Bully, Alvin and the Chipmunks, and Happy Feet, to name a few cringe-worthy examples.

It's no wonder then that students confuse storytelling with gameplay. It's the sizzle in the steak that advertisers know they can sell. But a good story does not a game make. At the heart of every game is a group of core mechanics - the things the player can do in the game. With a strong enough set of central mechanics, a game is still fun even without a story. For proof of this concept, think back to the popular games of your childhood - Centipede, Yar's Revenge, Super Mario Bros., and Tetris, to perhaps name a few. These games have limited narrative elements, if any at all. Yet despite a profound lack of story, they are still fun.

Providing an adequate context can be a tricky thing, and students would be better suited focusing on more abstract games if they wish to become successful designers. After all, a thousand years from now, gamers may not understand what it means to be an Italian plumber, but they'll still be playing Go and Chess in their spare time. Put another way, which game do you think has the best chance of survival over the next hundred years, Halo or Sudoku?

Where story works best is in its ability to provide a context for what the player does. It's the frosting that makes good cake even more delicious. For example, without GLaDOS' clever voiceovers, Portal is still a fun game. Throw in that extra layer of storytelling, and suddenly you've got Game of the Year. For the player, story should answer the question "Why am I doing what I'm doing?"

Furthermore, story can add an emotional weight to a game, making it more relevant to players. The Final Fantasy series of games is an excellent example of this. Without the emotionally driven, high fantasy tales at the heart of these games, they are still decent enough role-playing games. But the well-crafted stories that provide a context for the weapons, characters, stats, and combat have created a top-notch franchise. In this way, story answers the question "Why do I care?"

The failure of "It's Based on a Story" is that it neglects what makes a game a game. For fledgling designers, it's far more important to start with solid mechanics, as opposed to stories.

Conclusion
So what's the big takeaway from this article? It's not that students make silly mistakes. In fact, it's the opposite. Students make very reasonable mistakes. All of them are committed out of a genuine love for the things they enjoy about games - combat, story, and the differences in genres, to name a few. In time, perhaps these ideas might become commonplace, but for now, they are pitfalls best avoided.