The Battle of Gimlick Valley was a historic event between the Fongoid tribes of Gimlick Valley on Planet Morklon against a band of Agorian warriors. The Fongoids and Agorians were led by two famous leaders, Zahn Gribnak and Commander Argos, respectively. It was an important event in Fongoid history.
Zahn Gribnak was the leader of the settlement in Gimlick Valley, where all the Fongoids lived in peace until a band of Agorians from the Bernilius Sector invaded and attacked. Desperate, Gribnak bravely led a retaliation of poorly equipped and under-trained soldiers against the Agorians and ended up being captured, briefly pardoned, captured again, and finally killed. As a final act to get rid of the Fongoids, the Agorians destroyed the floodgate of the valley and the settlement was destroyed in the ensuing surge of water.
Ten years later, Nefarious used the Asteroid Flinger 5000 to send Ratchet and Clank flying through space, eventually crash-landing on Morklon. The planet became covered with a derelict swamp, with only one surviving Fongoid who appeared to have gone slightly mad. After the Fongoid explained about the demise of the settlement, Clank quickly thought of a way that the duo could obtain a ship to travel back to the Nefarious Space Station.
Clank contacted Sigmund to activate a time portal in a nearby time rift so that they could go back ten years to defend the outpost.
Stepping back in time, Ratchet & Clank saw the settlement how it used to be: a lush and vegetated settlement being ravaged by Agorian invaders. A young Fongoid child, later revealed to be the Fongoid the two had talked to as an adult, spotted Ratchet and asked him to help them. Ratchet proceeded to do so, taking out many Agorian troops and freeing Zahn Gribnak from captivity. After defeating two Hydra Tanks, Ratchet realized that the battle could not truly be won unless Commander Argos was taken out. There was no way to reach the top of the floodgate to face Argos, so Ratchet used his prior experience of time travel to plant some vine seeds. Amazingly, one of the vines from the present had grown straight through the time portal and led straight up to the floodgate, prompting Clank to comment on how astronomically small the chances of that happening were. After riding the vine from the present, Ratchet found his way to the floodgate and faced off against Commander Argos, an Agorian general who was piloting his Class 3 Agorian Space Cruiser. Argos was defeated in the following fight and his ship ended up sinking to the bottom of the river. As a way to repay the heroes for what they had done, Gribnak said they would salvage the Agorian ship from the river even though it could take some time.
Traveling back to the present, the victory of the Fongoids had changed the valley to a populated and thriving settlement. The present was actually a day of remembrance of the battle, while Ratchet and Clank were initially mistaken for actors due to take part in a re-enactment of the battle. Three statues were built in the settlement as well, depicting and honoring Zahn, Ratchet, and Clank. The Fongoid they originally talked to remarked how the pair seemed familiar and then let the duo borrow the ship so that they could travel back to stop Nefarious from reaching the Great Clock.
- When going around the settlement in the altered present, Ratchet can hear Fongoids teaching their children about the victorious battle as well as making impressions of Argos' last words. They often refer to Clank as a talking lunchbox, but one mentions that Clank is the son of Orvus.
- Despite Clank's strong belief that time should not be changed under any circumstances, it is his original idea to change the past of Gimlick Valley that ends up helping the duo to leave Morklon, but this may be an exception because there was already a time portal, so he may have meant that time cannot be changed directly by the Great Clock.