Before we learn about Starcraft 2 Overlord strategies we should first try to define or rather explain what an overlord is. This is the supply unit of the Zerg which of course makes it similar to the supply depot for the Terran and the Protoss pylon. It is used to provide supply in order for more units to be created. Thus it is necessary to build them.
One of the most crucial things to note about the overlord which is being used in the game StarCraft 1 compared to that being used in the StarCraft 2 is that they have a longer detection ability. This means that there is a need for the player to upgrade these units into overseers in order to gain mobile detection. It is advisable to place overlords behind the natural expansion base of the opponent early in the game in order to gain vision and information. They can also be used to scout the opponent's main base.
It is also good for the players to spread the Overlords at an early stage so that upon them reaching the Lair tech, they will be able to make use of the creep capability. This will enable them to expand the creep giving the Zerg an advantage in the game.
The best player who usually follows Zerg tactics will of course know at what time to use the overlords to generate more vision. To detect attacks, it is recommended for the player to place them in a curve when the anti air threats are low so that they can act as an alarm or a warning system in case of attacks from enemy lines. It is advisable to place them across a section of the map in a curve so as to enhance their efficiency.
They can even be used to patrol so that they can see enemies before they approach. They will also be able to spot pushes and aerial drops from the enemies. They should normally be hidden from the enemy ground units so as to avoid being spotted. This is because they move slowly until their movement upgrade which means they will have a hard time avoiding enemy fire if detected.
They are also used to generate creep once a Lair is created. By using the hotkey G on the keyboard the creep will be generated beneath and will be able to spread for an area of around two by two. This will enable a Zerg player to strengthen his or her units in the important areas within the map. They will also prevent Protoss or even the Terran gamers from creating buildings on the Creep.
To be able to morph an overseer, one has to use the hotkey V with an overlord selected. This transformation will last for seventeen seconds. This requires the existence of a Lair.
Once ventral sacs have been researched from the Lair the overlord will be able to transport Zerg units. The pneumatized carapace upgrade is also researched from the Lair and it increases the overlord's and overseer's move speed.
When playing against the Protoss, they can be sent to spy on the base of the opponent but they must be removed in time before they get sniped by the first stalker. Avoiding stargate units should of course be one of the priorities when controlling an overlord.
Starcraft 2 Overlord tactics are also rather beneficial when playing against the Terran. They can for example generate a discreet creep within a location which is not being monitored. By building a hidden building like a spire within this Creep, they will be able to avoid the scan from the enemy Terran.
In a Zerg versus Zerg engagement neither player normally uses units that can attack air units and so it's usually safe to spread out your overlords across the map. The enemy Queen units should however be avoided.
