Creep Mechanics | Zerg Creep Guide

[Kreeper]

This creep guide for Starcraft 2 gives in depth information of how to best utilize creep within Starcraft 2. This guide will break down the benefits of using creep to your advantage as a Zerg player.


I have figured out most of how creep works behind the scenes, including:

1. What are the benefits of Creep?
2. How does Creep Grow?
3. How do you optimize Creep Growth?

The first half of this guide is likely to look a lot like the liquidpedia page on Creep in Starcraft 2. This is just to ensure the basics have been covered before explaining the rest.

The Benefits of Creep :
Before anything else, we need to understand exactly what benefits creep gives. The major advantage of creep is speed. It increases the movement speed of all zerg units by 30%, with a few exceptions. Queens move 170% faster. A Hydralisk moves 50% faster. Both Crawlers move 150% faster. The other benefit is the ability to place zerg buildings, including Spine and Spore Crawlers. It also prevents these buildings from dying, as will happen if they are not connected to creep.

On Vision :
creep =/= vision, is important, because for example your hatchery doesn't have vision about a tile and a half within the edge of its creep. This means the enemy could sneak over the edge of the hatchery's creep and not be seen at all.

Lair's and Hive's do not increase the creep range, but increase the vision range +1 each time. With Lair's the enemy can still barely step over the edge of the Lair's creep and not be seen. With Hive's the vision goes beyond its creep range, so a unit could be spotted even off creep, if they are near it.

Check this thread too: Tumor's creep spread rate - Page 2



How Creep Grows

Creep is generated by 4 sources:
- Hatcheries make the largest creep area in the game, but are not an economical way to increase creep size.
- Overlords, with Lair tech, have a "Generate Creep" ability. This creates what is usually referred to as a "2x2" area of creep.
- Creep Tumors will generate a "4x4" area of creep. Due to the way creep tumors are usually placed (at the end of a currently existing bit of creep), they generally only generate a bit more than half this amount.
- Nydus Worms will generate a "4x4" area of creep after emerging from the ground.

Now, this "4x4" area, and "2x2" area are both misnomers. Creep actually generates in a "Squared Circle" pattern, with a radius in what I will call Distance Units. A Distance unit is the smallest whole unit defined internally in Starcraft. The length of a distance unit is approximately the length of a zealot. In addition, I will define a Square Unit as a 1 Distance Unit by 1 Distant Unit square area. This is approximately the total space a Zealot takes up.

A Creep Tumor generates creep in a 10 square radius squared circle. This means it generates creep in a total of 292 squares. An Overlord generates creep in a 6 square radius squared circle. This means it generates creep in a total of 96 squares.



Why are these numbers important? Well it turns out that how long it takes to generate creep is well defined.

• Creep doesn't start being generated until a delay period. On Overlords, this is 2 seconds. On Creep Tumors, this is 0 seconds.
• Creep is generated every Creep Generation Period. The Creep Generation Period of Overlords is 1 second. The Creep Generation Period of Creep Tumors is 0.8332 seconds. At the end of each of these periods, just less than 3 square units of creep are created on average (about 2.835, based on observations detailed below).
• Creep is generated randomly, so long as it is adjacent to existing creep. This is how the cool growth effect works internally. This has a hidden ability in it though: Multiple creep sources generate simultaneously.
• I've run some tests on exactly how long it takes for an Overlord and Creep Tumor to fill the area defined above. These tests are based on 10 trials.
• An Overlord takes about 34 seconds to fill up its entire area. Judging by how its creep generation is defined, 34 seconds is likely the exact value.
• A Creep Tumor takes just less than 86 seconds to fill up its entire area. Judging by how creep generation is defined, it is likely 85.8196 seconds exactly.

But what if we want this faster.

How to Optimize Creep Growth :
The key to optimizing Creep Growth is hidden above. The easiest and quickest way to optimize creep growth is to add more creep sources. The time it takes for two Creep Tumors to fill an entire area is about 43 seconds. The time it takes for three is about 29 seconds.

As you can see, there are diminishing returns. Thus we have to question exactly how fast we want it, compared to what it costs. Since Overlord creep generation is free (unless the overlord is placed in danger because of it), we will ignore it for the purposes of optimizing (just grab a group, have them all generate creep, keep them together).

When you generate creep edge to edge, you tend to save 124 square units. This translates into saving about 36 seconds on one tumor. On two tumors, the amount of time saved is actually halved, since you would have generated it twice as fast. Thus you save only about 18 seconds, and it takes about 25 to fill. With three, you would only have saved 12 seconds, and it would take 17 to fill, etc.

So exactly how much is optimal? Well EDIT as of the Beta coming back up, Spawn Creep Tumor now takes 15 seconds to build the tumor, and 30 seconds for the cooldown. This means that you should never, ever, have more then two creep tumors together, unless you need creep somewhere that instant.

The other main way to optimize creep growth is having multiple paths. You do not need a single line, and generally it is beneficial to have creep covering as much of the map as possible. This obviously increases the amount of micro required to keep the creep up, but each path basically consists of the problem above.