Beast Rizer 7

Petropolis 8 (ペトロポリス8) is a 2004 beat 'em up video game developed by D3 Publisher and published by Namco and Nick Games. It is the fourth handheld game in the Petropolis series and the second to be released for the Game Boy Advance. Unlike Pocket and Super Shock, Petropolis 8 features the ability to play two characters in a partner setting.

Story
Sometime before the events of the game, a witch named Rosetta builds a gargoyle assistant based upon 395's remains named G-65. G-65's designed to be a loyal, obedient copy of 395. As such, he can learn new attacks, and can meld himself seamlessly with miniature creatures known as morphmen. Rosetta has gathered nine other specimens for her experiment, but one of the morphmen escaped underneath her watch to warn someone about the witch's nefarious scheme.

The morphman escapee ended up in the residence of Thunder Storminski. The coyote noticed the morphman injured and treated its injuries. After he was healed, the morphman (which Thunder named Yolk due to its yellow skin) warned him about Rosetta about to unleash her army of mutants upon the islands. As if on cue, Rosetta begins to launch her attack on the Petro Islands, and Thunder and Yolk outrun the mutants and hurry to Julie. When they finally made it to her house, the vixen ask why Thunder is wearing a single glove. It turns out that Yolk transformed himself into a glove which upgraded the coyote's electrical aim. Willing to save Yolk's morphmen friends, Thunder and Julie begin to search for their friends and the source of the trouble (which is the separation of the Sacred Orbs from the Dragon Temple).

Veterans

 * Thunder Storminski w/ Yolk: Gains other morphmen throughout the game which changes how he uses his Electric Badge powers.
 * Julie Vixen: Uses her 1-Love Pistol, among other weapons.
 * Fluff Cotton: Uses his jumping abilities and speed.
 * Selene Melodia: Plays as she does in Petropolis Super Shock, but has access to two new elements (dark and water)
 * Burrow Diggs: Performs "Gravity Dashes" when charged with enough energy into his Anti-Rings.
 * Whirlwind Spinner: Can fly into his enemies and can hover for a limited amount of time.
 * Pyro: Fights his opponents with his usual Flare Balls and claw attacks.
 * Betsy Spots: Plays her Venom Guitar to unleash poisonous spikes.
 * Gul Darkshell: With his Skull Cap, he can summon the dead to fight for him.

Newcomers

 * Lucky Stemling: A ferret girl with a cool personality. She is the daughter of an archaeologist who recently studied about the morphmen. She was sent to rescue the morphmen and send some of them to her father for research. Lucky uses her yo-yo to fight against the mutants.
 * Rosetta: A witch from the Giant Islands. She was banished to the Petro Islands due to her dangerous experiments. When she discovered the morphmen and 395, she decided she can use them to create an army of mutants to take over not only the Petro Islands, but the Giant Islands she used to call home. She even steals the Sacred Orbs from the Dragon Temples to further escalate her plan.
 * G-65: A gargoyle who follows the orders of Rosetta. He is actually 395, but fused with one of the morphmen from the Ancient Isles, which turned him into the being he is now. In the true ending (if the player collects all eight Sacred Orbs), after his defeat G-65 attacks Thunder, causing the eight Sacred Orbs he has to scatter. He uses these orbs to fuse with the Ancient Isles and all of the morphmen on it, becoming a fearsome monster. However, Thunder and Yolk use the Sacred Orbs to become Super Chimera Thunder and successfully defeat him with the help of Rosetta. Eventually, Julie finds G-65's damaged body on a tree and fixes the gargoyle. The game ends with the new G-65 playing with Shelly.
 * Super Chimera Thunder: A new form Thunder takes when fused with Yolk and the power of the Sacred Orbs. It resembles his original Chimera form, but has the height of a normal teenaged beastman.

Stages

 * Route X
 * Applecrest Isles
 * Undersea Fortress
 * Volcanic Crater
 * Magical Carnival
 * Sparkling Winter
 * Robotic Ruins
 * Sacred Ancients
 * Morph Temple
 * Despair