It starts with the Gang of Seven playing some sort of "Dino Football" in the Great Valley.

Then their ball is kicked all the way to the Mysterious Beyond. They run all the way to there but are chased by Sharptooth from The Land Before Time 1 until he trips over a single atom and falls 30,000 feet to his death.

Then Chomper's parents, who are now voiced by Clancy Brown and Reba McEntire, appear and have a conversation with Chomper like in The Land Before Time V: The Mysterious Island (this time in Flattooth and changing the word Longneck into Yellowbelly).

Then they go to Berry Valley where Doofah ate all the berries.

However, Ourano Shrek (an Ouranosaurus) appears and says "WHAT ARE YA DOIN IN MY SWAMP" and then Alberto Scat (an Albertosaurus) kills Chomper and his parents, who die instantly from his 10000000000000000 frequency roar. However the rest of the gang somehow does not die.

Then the Flossing Euoplocephalus shows up and makes the gang and the Yellowbellies do the floss and then they chase them all the way to a cliff.

Then the Gang of 6 and the Yellowbellies dance the three off a cliff and then the Gang of 6 goes to the Big water and drink the entire ocean until they are huge planet sized balls filled with water.

Then Spike burps and releases all of the water and collides with the gang, who also release all of the water and they fall 1000000 feet into Berry Valley. Then all the Yellowbellies feed the Gang all the berries in Berry Valley