"A Hen-Hen specially bred for extra protein by the Tabby Army." - The Slimepedia
The GMO Hen is a rare kind of Hen-Hen found only in The Tabby Fortress and The Tabby Barracks.
The GMO Hen can breed like any other hen, produces GMO Chickadoos.
It is one of the 2 favorites of the Tabby Soldier, the other being the Stony Hen.
It is easily recognizable by it's unique coloration and maroon spots.