The Mogu and the Trogg is a book found at several locations, including the northeast corner of the lower level of the Scrollkeeper's Sanctum, Temple of the Jade Serpent, Jade Forest, and at the feet of Lorewalker Huynh in the Seat of Knowledge, above the entrance to Mogu'shan Palace in the Vale of Eternal Blossoms. It contains the origin story of the grummles and a parable that is somewhat based on their role in the overthrow of the mogu.
"What strong arms you have," said the mogu to the trogg. "I shall use my magic to make them stronger, so they may crush my enemies."
"And what a mighty nose you have," said the mogu to the trogg. "I shall use my magic to make it powerful, so that it may sniff out my enemies."
"And what a good sense of direction you have," said the mogu to the trogg. "I shall use my magic to make you never forget a trail, so that you may learn the paths of my enemies."
The mogu used the very waters of the Vale of Eternal Blossoms to shape this creature in to a weapon.
When the smoke cleared and the dust settled, what should the mogu see? But a grummle, standing there gleefully.
"With strong arms, and powerful nose and mind that never forgets a trail," said the mogu to the grummle, "take this food from the farms of the east to the wall of the west. Find every trail in between and tell me of the enemies you see."
And so the grummle went, with arms of strong and nose of a tool and mind that never forgets, to look for "enemies", this word the mogu used. And deliver food he did and looked for trails but not an enemy found.
"What news of my enemies?" said the mogu to the grummle. "Do they hide in the mountain passes? Do they hide in the caves near the river? Do they hide in the fields of the farmland?"
The grummle blinked and thought. He thought and thought and finally spoke: "I smell with nose and look with eye but no enemies of yours did I spy. In the mountains I saw hozen, carving their little tunnels. In the caves near the river I saw the jinyu, speaking to their water. In the fields I saw the pandaren, dancing a funny dance."
The mogu pondered this, and grew relaxed.
Many times the grummle would leave, and each time the mogu would ask him the same question when he returned. And the grummle's answer was always the same.
What the mogu did not realize, was that the hozen were building their tunnels that would lead them behind the mogu defenses. The jinyu listened to the waters to divine where the mogu would first respond when the rebellion started. And the pandaren were not dancing, but training to fight unarmed.
When the rebellion began, the mogu was outraged by his surprise.
"You said you did not find any enemies of mine!" said the mogu to the grummle.
With a grin and a smile, the grummle said to the mogu: "I saw what I wanted to see. You heard what you wanted to hear."
- Patch 5.0.4 (2012-08-28): Added.