Game Balancing - Fundamentals of Game Design - page 342

an enemy more difficult to defeat, in absolute terms, than the trivial enemy that
established the baseline. In effect, the absolute difficulty of a challenge equals the
intrinsic skill required and the stress of the challenge compared to the trivial case .

You will find the concept of absolute difficult y usef ul when you need to compare
the difficulty levels of different challenges. In general, if one enemy has twice as
many health points as another, all other things being equal, it survives twice as
long under assault, making it twice as hard to defeat.

RELATIVE DIFFICULTY AND POWER PROVIDED
You cannot determine how the player perceives the difficult y of a challenge
through absolute difficulty alone. You must also take into account two more fac-
tors. The first is the amount of power that the game gives to the player to meet the
challenge. Power provided measures, by means appropriate to the situation, the play-
er's strength: the health and powers of his avatar, the size and makeup of his army,
the performance characteristics of his racing car, or whatever factors apply. In the
simple example described in the previous section, power provided would refer to
the amount of damage the avatar can do when hitting the enemy and the avatar's
resistance to damage: the number of health points that he has to lose before dying.

NOTE Power pro-
vided is not related
to native talent: It is
a factor you control.
In some games, the
power provided may
change through the
action of positive
feedback.

The relative difficulty is the difficulty of a challenge relative to the player's power to
meet that challenge. For example, in an RPG, a player playing a level 1 knight will
find it much harder, in absolute terms, to defeat a large enemy than a small one.
But a player playing a level 5 knight won't find it nearly so hard to defeat that same
large enemy because the game provides a level 5 knight with so much more power
than it provides a level 1 knight.

If the power the game provides to the player doesn't change throughout the game,
then you may ignore this distinction between absolute and relative difficulty. But
most games include an upgrade progression whereby the player gains power as the
game progresses because the new powers keep the player interested in the game and
give her the feeling of accomplishing more. As a result, when level designers build
challenges into the game world, they must also take into account the power pro-
vided to the player to meet those challenges. The level designers have to know, for
example, that by the time the player reaches the fourth level, he will have earned
three major weapon upgrades and a faster vehicle, so they set the difficulty of the
fourth level's challenges relative to that level of power provided. To simplify man-
aging the difficulty, many games don't allow the player to carry powers over from
level to level; instead, the level designers themselves set the amount of power pro-
vided separately for each level and take it into account accordingly as they devise
challenges. In persistent worlds, in which each individual player has his own
amount of power provided, earned through his earlier play, the game must either
warn players in advance against trying a mission that is too hard or flatly exclude
them from such missions.