From Liquipedia Starcraft 2 Wiki
|Description||Prototype harvesting unit. Gathers minerals more quickly than regular SCVs. MULEs last 90 seconds before their systems fail.|
|Defense||60 0 (+1)|
The Mobile Utility Lunar Excavator (MULE) is a temporary unit that can mine minerals and repair for the Terran forces. MULEs are called down from the Orbital Command at the cost of 50 energy. They last 90 seconds of game time, or about 65 seconds on "faster" game speed. If the MULE is cast on a mineral patch it will begin to mine minerals as soon as it spawns.
Despite their timed life and Orbital Command energy cost, a MULE has several advantages over an SCV. A MULE costs no supply. MULEs have a mining time 2.05x longer than an SCV, but have the same movement speed and acceleration. MULEs carry 6 times more minerals per trip than an SCV on normal minerals, gathering 30 minerals per trip on all types of mineral patches. Their timed life allows 8 or 9 mining trips which totals 240/270 minerals respectively on any mineral patch. This works out to 160/180 minerals per game-minute. A MULE can mine a mineral patch alongside an SCV thus providing extra income on expansions that are already saturated. Any number of MULEs can be set to mining a base at once.
MULEs are as effective as around 4 (±0.3) SCVs, as SCVs average 42-43 minerals per game-minute on blue mineral patches (for two or less workers per patch).
 Mineral Patches and Mining Distance
It has been noted that the placement of mineral patches on certain Blizzard maps can cause a MULE to mine suboptimally depending on the patch it is ordered to harvest. Specifically, on mineral patches with optimal placement, the MULE will mine and return its cargo nine times providing the player with 270 minerals before the MULE expires. Yet on the farthest mineral patches the MULE will only complete mining eight times, returning a total of only 240 minerals before being destroyed--an income reduction of 11%. It has also been shown that in a few instances, the placement of a mineral patch will actually cause the MULE to complete mining nine times but only return minerals eight times before being destroyed, resulting in 30 minerals being destroyed completely.
It is therefore recommended that players take note of which mineral patches are "optimal" on each map to ensure maximum efficiency from the use of MULEs.
 Gold Minerals and Balance
In the fall of 2011, GSL announced that many of the maps for GSL November would have Rich Mineral Field patches removed. It had been speculated by some members of the community that MULE usage on high yield mineral patches was responsible for the high win rate of Terran players in certain tournaments. Because MULES harvest 42 minerals per trip on high yield patches, it is thought that Terran players may gain an advantage by placing their MULEs primarily on high yield bases. This sentiment was reflected by Blizzard Balance Team member David Kim in his February 2012 "Situation Report". Kim said that in Patch 1.4.3, MULEs will only mine 30 minerals per trip from high yield mineral patches--the same amount that they mine on regular mineral patches. This change was present in Patch 1.4.3 upon its arrival.
 Competitive Usage
MULEs can be called down anywhere on the map if the player has vision of the area. There are few instances where doing so in order to scout or repair damaged units would be worth the loss of economy, especially with Scanner Sweep costing the same amount of energy. They can be called down for repairs in the field.
Dropping MULEs in your opponent's base can also be used to humiliate a losing opponent, coercing him to concede.
 Vs. Protoss
 Vs. Terran
MULE can be used late game when resources aren't as much of an issue in an "all out" type of battle. Call the mules down on enemy tank lines as you move in in order to draw tank fire and allowed enemy tanks to splash damage each other. This is especially good if you can time it right and put that first round of fire from enemy tanks on cool down right as you move in to get that extra edge in the battle. This functions as an expensive Terran version of sc1:Zealot Bombing.
 Vs. Zerg
The Griffith 4OC build takes advantages of MULEs by quickly committing to 4 Orbital Commands. The build provides Terran with a fairly significant mid-game economic advantage.
- MULE's sounds (video and sound) - YouTube video.
 Patch Changes
|Patch 1.4.3 (version 126.96.36.19929)|
- The MULE and the Metagame Shift - Article on TeamLiquid.
- Analysis of MULE and SCV use - Article on TeamLiquid.