Fossil Fighters Cheats
The 3 Guh Robots
Use the time machine and defeat the 3 Guh Bots at another time to unlock them.
Dynal, Duna and Raptin
After you get the time machine, defeat him in his starship.
Beat the game and then defeat the three main BB bandits to unlock Frigi.
Beat the game and then defeat Saurhead a set number of times to unlock Igno.
Squik and his other elements
Get all vivosaurs to rank 12 to unlock Squik and his other elements.
After you unlock Parchment Desert, talk to the old man. He'll talk about an oasis seed. You have to buy four of them, which costs 80,000. After they are planted and have grown you can find T-Rex fossils at the Northeastern part of the desert. Note: They're very hard to find. Also, the person in the guil has them as a Today's Special.
After you beat the game if you go to the park area you can find Medal-Dealer Joe. He sells Tryma fossils for 9,800 each. Note: Tryma is weak, but you still need him if you want to collect all the Vivosaurs.
How To Get Frigi
After you beat the game, go tot he BB Base. Go to the last room and talk to Vivian Rex or Snivels. They will ask you to battle them. If you beat all three of them in a row you'll get a message saying that Frigi was loaded into your VMM.
Guhnash's Three Brains
After you complete the game, if you go back to the secret warehouse where the warp machine is, you should see a second machine. Talk to Dr. Diggins and he'll say he's working on a time machine and that he requires three parts: Goldonite (get it from Nevada in the DigaDigamid), A Diver's Watch (Captain Woolbeard has it), and an Idolcomp Component...
How To Get Igno
After you beat the game, go to the Fossil Stadium. Go into the common room and talk to Saurhead. You'll have to fight him three times in a row. If you beat him all three times you'll get the message that Igno was loaded into your VMM.