First Victory
After defeating the first of either Genesis or Oblivion, you'll be teleported to the Ferme Yamashita, in the Village Mimiga. After a brief cutscene with Sue, Curly, and Booster, you will be given the ●BOOSTER v2.0●, allowing you to fly around faster, and in any direction.
Second Victory
After both Genesis and Oblivion have been defeated, you will be teleported to the island's Noyau. Balrog will be found nearby, and he will offer to trade your ●FIREBALL● for Curly's ●MACHINE GUN●.
Afterwards, head to the left to wind back up in the Revolutionarium. Make your way back to the Village Mimiga however you see fit. When you return, head to the Hôtel de ville and speak with Booster to receive a key for a pair of new rocket platforms in the Cheminée and Conduit.
There are two new locations you can travel to, depending on where go: The Incubateur and Paroi Extérieure, or The Jardin du diable and Terre Jadis Sacrée.