| Animal Information
The Grumpisaurus is one of the dinosaurs that Dr. Crab created.
Dr. Crab stole the Foreverlution Formula from Dr. Claude Kane II which he used to bring dinosaurs mixed with human DNA from his relatives to life. The Grumpisaurus was one of these dinosaurs. Grumpisaurus stepped on Radioactive Man, then complained when Radioactive Man called him an "old fossil". The Grumpisaurus then ranted at Radioactive Man about how his species should still be the dominant species if it wasn't for the comet and the ice age. He then turned around to look for food and hit Radioactive Man with his tail as he did so.
When Dr. Crab's base was destroyed the island sunk into the ocean, leaving the dinosaurs in the water.