Thursday, 23 April 2009

Cave Full of Spiders Retrospective

Cave Full of Spiders was my first game, created out of the course of about a month, in order to fulfill my goal of actually completing and releasing a game.

To this end I made some absolute decisions about the fundamental nature of the game-
  • To minimise the use of graphics and sound
  • To focus on having simple gameplay mechanics
  • To make level design the primary focus of the game
  • To have at least one mechanic which would set the game apart from most

Coming from these decisions I went with the following strategies for my work-

Graphics would be extremely simple, I would spend as little time working on them as possible in order to free up time for more inportant things.

Sound, if there was any, would only be added at the end of the development cycle.

The game must be extremely easy to learn, and have absolute rules, leading me to use one hit kills for all entities.

Part of the reason for developing Cave Full of Spiders was to show off my level designing ability, so to this end I created a set of easy to understand traps and features which could be used in multiple ways, the small play area also made level design extremely quick, although it did have one majoer problem, to be explained later.

As far as game mechanics which would help make the game something special were concerned, I'd been considering a game with destructible terrain for some time, and liked the idea of an underground setting, but so far all my ideas had been for open ended platformers. When I started experimenting with destructible terrain, I realised how well it could work from a top down perspective. This then evolved into the overall idea for CFoS. Visually, my low detail graphics were perfect as there were no issues of sprites lining up or the like due to their flat colour nature.

The game concept

I didn't come up with a big design document for the game, partly because I was really revved up about doing some level design, but also because the idea was so simplistic it didn't take much explaining. The rules were these.
  • The player starts at a point in the level and must get to another point (the ladder).
  • Obstructing the player from reaching this goal are two main obstacles- Spiders and rock
  • Spiders will constantly attempt to move towards and collide with the player. Collision with a spider kills the player (they lose 1 life and restart the level).
  • Rock comes in two types, normal and hard. Normal rock can be cut through by using the player's weapon and firing at it, causing it to erode away. Hard rock is invulnerable, and serves as a way of defining the play area and setting particular routes the player shoudl use.
  • Gold nuggets are scattered around the levels. The general idea of this was to make most levels relatively easy to solve without obtaining the nuggets, but if the player wanted them they would have to face further dangers. The nuggets gave the player a big score boost, but were limited in their desirability, as well be explained further later.

This was the basic structure of the game. The player would arrive in a level, then have to cut through rock and avoid spiders to reach a ladder to the next level, throughout which they would have the opportunity to obtain gold nuggets and a higher score. I added other features after this to make things more interesting for both myself as the designer and the player.

  • Lava which would kill the player or any spiders on contact. This adds an environmental threat to the game.
  • Dynamite explodes when shot by the player, destroying any spiders, rock or players within the explosion. This serves the purpose of being a risky weapon against the spiders, as well as allowing rapid destruction of portions of the map.
  • Magma is like lava, but it expands from a central point for a period of time, and after a while it disappears. This has the same effects as lava, but is more dangerous as it expands to fill any space it encounters. This feature in particular caused me a lot of problems. For starters, it was originally supposed to be water, which would drown spiders but allow the player to live, however after extensive playtesting, this felt way too powerful, as the player could stand in the middle and a wave of death would slowly expand from them and kill everything within range. Additionally, it was intended to expand in much smaller increments, but I was unable to stop it from consuming exponentially greater amounts of processing power with each generation and eventually freezing the game. Thus I changed it to magma which killed both the player and spiders, and expanded in even segments, making it both a weapon and a threat to the player.
  • Crystals were added late in the game as I tried to come up with more interesting designs, I decided to add an item that would make the player temporarily invulnerable, but still to design the levels to they could use it to either get to safety or to get to more gold.

With this limited but fairly balanced set of features I assembled each of the games maps. Level design was pretty easy, and by having a general idea for each level, it was quite easy to put them together and make something that worked. The after testing the maps could be tweaked to balance them a little.

After I'd developed most of the maps and created 90% of the game, I decided to add a little story. It wasn't much, but I think it really added something to the game. I also added a quick explanation of how to play the game that would show before the player started the game, to make sure that the player would not be confused by anything in game.

Patching things up

Shortly after releasing the game, a bunch of bugs were discovered, things I'd missed due to my decision to test the game singlehandedly. I returned to these and fixed them, and added new features, such as a pause button, and ambidextrous controls, so you could use either WASD or the arrow keys to play, and either click would fire the gun. As soon as I released this I realised there was another exploit: now the player could use both control sets simultaneously to double their speed or firepower. I set about fixing these and finally managed to release the game as officially bug free.

What went right with Cave Full of Spiders
Rapid development-
By streamlining and minimising the graphical and audio aspects if the game, I was able to focus on design and programming, meaning I could get to the fun stuff very early on, and develop the entire game ove the course of a month (of course, the amount of free time caused by my recent redundancy also contributed top this).

Level design-
I thoroughly enjoyed working on the design for these levels, and found it a lot easier than I expected. The balanced feature set and absolute rules made it easy to design a variety of level types, and the destructible terrain meant that most of the levels could be completed in various ways. Introducing new features incrementally would also mean the player was not overwhelmed, nor would the game become overly repetetive.

Simple gameplay-
The game, in my opinion, is very easy to learn, and follows the same kind of rules throughout the level.

What could have been better
Greed mechanics-
The optional gold nuggets, while often tempting, don't give the player anything other than a score boost, meaning that they can easily be ignored by a player focused simply on reaching the exit. I wanted originally to implement online high scores, but it proved to be beyond my understanding, and was never achieved. Had this been in, the mechanic would have been more effective as it would have given an element of competition.

Little maps-
Though having a small play area accelerated the design process, it meant I was fundamentally limited in what I could achieve. By the time I'd reached my level quota I felt that any more maps would have been repeating elements of the old ones.

I know it was deliberately neglected for the purposes of rapid development, but the sound it honestly quite poor. I added a little piece of music to the game recently, but it's still nothing special.

Cave Full of Spiders can be found in a link to the left if you wish to know what the hell I was just writing about.

1 comment:

  1. Very nice postmortem. You've definitely brought up some things I will consider in my own game design.