The original Long Cat image.
The image of a random white cat being held by his legpits immediately soared to popularity once it became known. Many savvy interweb-goers now associate this image with the almighty Ceiling Cat releasing his epic ceiling powers.
About
Have originated on 2Chan, but this claim has not been confirmed.
Catnarok/Tacgnol
Within the Catnarok mythology it is believed that one day Longcat will engage in a mighty final battle with his anti-self, Tacgnol (Protip: Longcat spelled backwards).