Krool’s Forces: Sweetening the Challenge - The Game Maker's Companion: Game Development - page 104

Challenging Ingredients
We already have a movement mechanic that turns our level into an interactive playground, but
we don't have something we could call a game yet, because we haven't provided the player with
any challenges. The original game provided a range of challenges relating to the various short-
and long-term goals of the game (including the role of Krool—see Figure 5-1). You will have
already started to discover the back story behind the game through the Zool comic strip, and the
overall goal of the game is described in the original Amiga manual as follows:
In Zool you play the interstellar cosmos dweller from the N th dimension. You must guide
Zool through thousands of screens of surreal and bizarre action in a bid to bring the
intergalactic Ninja back home to the N th dimension. You must take Zool to the outer
limits of the known universe, through quite a bit of the unknown universe, and beyond
the “fairly well-known, but I wouldn't want to walk through it at night on my own”
universe.
Before reaching home, Zool has to successfully work through all manner of bizarre
situations, worlds and enemies. The only way to do this is by exploring each world until
the exit is found, and progressing onto the next one.
So, the long-term goal is to get Zool back home, and each level has a medium-term goal of
finding the exit. Simply adding an exit to our existing level would technically provide the missing
challenge required to call it a game. Nonetheless, reaching this exit could actually be pretty
unchallenging unless there were some additional constraints. We can describe the constraints
from the original version of the game as follows:
• Movement —The exit is placed in a position that is difficult for Zool to reach, requiring
him to employ a full range of movement mechanics in order to get to it.
• Bonus Collection —The exit is unavailable until Zool has collected a certain
percentage of the bonus pickups on each level (25% on easy, 50% on normal, and 75%
on hard).
• Enemies and Hazards —If an enemy, enemy missile, or hazard touches Zool, then he
will lose one bar of health. However, Zool can destroy enemies by shooting them with
missiles, sliding or spinning into them, or jumping on top of them.
• Lives —Once he has lost three bars of health, Zool loses a life. He starts with only three
lives with which to complete the game (the original game had continues too, but we
will ignore these in our version).
• Time Limit —Zool has a limited amount of time to reach the exit before he loses a life
(the time limit depends on the difficulty setting and the level).
The goal of reaching the exit under these constraints characterizes the challenge of Zool as a
game. Including them in our version will not only make the game more fun, but will make it
recognizable to players as belonging to the Zool series. Many of these features will be relatively
easy to implement, but there are some challenges ahead for you , too. In this chapter, we will
concentrate on bonuses, enemies, and hazards, and in the next (and final) chapter on Zool, we'll
deal with lives and time limits.