In Fossil FIghters: Champions, Joe Wildwest gives you an option of four vivosaurs. These vivosaurs are the air type, Aeros, the fire type, Dimetro, the earth type, Tsintao, and the water type, Toba.
Each of the vivosaurs specialize in different things, so choosing the right one is important if you plan on keeping your starter through the whole game.
If you are mostly a(n).....
-Up-Close-And-Personal Fighter: Aeros is recommended. He sports high LP and Attack. However, he lacks in a few other stats. Send him up front in the Cambrian formation to take out enemies in one to two hits.
"He's a power type that overwhelms foes with sharp claws" -Joe Wildwest
-Long-Range-Hitter: Toba is recommended. Toba, being a long range vivosaur, has some pretty high LP. But unlike a lot of longe-range vivosaurs, Toba's stats are actually pretty even. Place Toba in the back when using the Jurassic formation for some hard hitting. As a titanic, pairing Toba up with a vivosaur that has FP plus is a good idea.
"That's a fast-growing, well balanced vivosaur called the Toba Titanosaur. It's one'a yer more fashionable types." -Joe Wildwest
-Stellar-Stats: Tsintao is recommended. Tsintao can penalize enemies in the AZ with some fairly good stat effects. Having the link ability is also a plus. But as a close-range vivosaur, it is not wise to place Tsintao far in the far back of the Jurassic formation. A good idea would be to put Tsintao in the SZ of the Cambrian Formation, then rotate him to the front of the Cambrian formation to do some damage (rotate him back after attacking, of course). Tsintao does not have as high LP and atatck as Aeros does, so relying on Tsintao as your only fighter may not be the best of ideas.
"It's a backup-type vivosaur that has great support skills." -Joe Wildwest
-Mid-Range-Monster: Dimetro is recommended. Dimetro has low FP moves and great support stats like Speed, Defense, and Accuracy. He also has some good support. Putting him in the SZ zone is a great idea, as you will get his full power and his support effects. He is good in any formation, Jurrasic and Cambrian.
"It's a tricky technical type that confounds foes with special skills." -Joe WIldwest