Game Development Reference
In-Depth Information
Elegance Case Study: Predator versus Hellion
StarCraft II: Wings of Liberty
has two units on the Terran race with very
similar roles. The Predator and Hellion are both fast, mid-cost units that
specialize in fighting groups of small enemies by using area-of-effect
attacks.
But only the Hellion unit was included in the multiplayer game. This
was a good decision on the designers' part, because although the Predator
and Hellion units fill the same basic role, tiny differences between them
make the Hellion a much more elegant design. Let's look at why.
First, some stats:
Predator
Hellion
Speed
4
4.25
Hitpoints
140
90
Attack
Strikes enemies with
its front paws for 15
damage, and causes
a shockwave that
does 20 damage to all
units surrounding the
Predator at close range.
Fires a stream of flame
that does 8 damage to all
units in a line projecting
out from the Hellion to
medium range. Does
+6 extra damage to
Light units, increasing
by another +5 with the
Infernal Pre-Igniter
upgrade.
Delay
between
attacks
1 second
2.5 seconds
It's immediately clear that these two units are very similar. They are
both about twice as fast as a soldier on foot. They have similar health re-
serves, and they both damage enemies in an area. The main difference
is in the geometry of their attacks. Both do area-of-effect damage, but
the Predator does damage in a circle around itself, while the Hellion
does damage in a long, narrow stream. And that turns out to be a huge
difference.
