Your forces are under attack.

@Eeveeinheat  
What they said. Here, the musical version.

@FamusJamus  
Not enough minerals.  
Not enough minerals.  
Not enough minerals.  
Not enou- oh, forget it. If you didn’t get the message by now, you’re never gonna get it.
 

@Eeveeinheat  
In an RTS, you usually command units that you yourself produce by spending resources.
 
Since units are not the only thing that requires resources, and there should be room for error, resources are typically available in vast amounts all over the map.
 
This allows the player to create as many units as they want, which would quickly move the situation out of control and tank the system as it tries to handle all these units.
 
To prevent this, Starcraft, as well as other RTS games, introduces the concept of supply - an arbitrary units limit. The game uses this mechanic to tell you that you cannot have more than X units, roughly speaking.
 
The initial supply limit in Starcraft is really low, but it can be increased by building special buildings. In Starcraft, there are three factions, and each faction has a unique name for this building (or, in case of the Zerg, unit).
 
The name of this special building for Protoss (one of the factions, the appearance of which is mimicked by Rainbow Dash here) is Pylon.
 
When the player tries to perform an illegal operation, they are informed of the error by the ingame voice. One of these errors occurs when the player tries to produce units while they already are at the supply limit. If the player is playing as Protoss, the message they get is “You must construct additional pylons”.
 
And the rest is a fusion of the phrase’s qualities, the fact that exceeding the supply limit is quite a common error, and other things I’m not sure of.
 
Hope that’s clear!

Out of no where, freaking zerglings.  

I don’t get it. Is this a game mechanic in Starcraft of something?

NOT ENOUGH MINERALS!

SPAWN MORE OVERLORDS!

My Life for Aiur Cider!

YOU REQUIRE MORE VESPENE GAS!

>see thumbnail to this pic  
>remembers me of my two words picture  
>135% mad  
>see uploader description  
fuck yeah

But I’m already at 200/200!

But I can’t fit any more in!