Those! is one of many unfinished episodes of Invader Zim. No complete scripts exists for this cancelled episode, and very little is known about it, other than that it involves Zim commanding an army of slightly-larger-than-normal ants. 
Details are unknown since neither the script or audio were ever finished and/or released.
The ants start off the size of a shoe, but grow the more they eat (like Peepi did in "Hamstergeddon"), and soon overrun Zim's lab. Zim finds his crashed Voot Cruiser and drives it into the lead ant's mouth, making it explode while covering Dib, GIR, and himself with goo. Afterwards, Gaz, who managed to stay out of it untouched, punishes Dib for drinking the last soda again. All the other ants die after the loss of their leader. 
"Those!" parodies the 1954 science fiction film Them!, which featured ants grown to giant size, after being exposed to nuclear radiation, attacking the Earth. A final idea was never settled upon.