Portal Fantasy revolves around collecting creatures called Porbles and using them in turn-based battles. Players travel to different locations, catching these Porbles and combining them using a fusion system to upgrade them. This mechanism allows the creatures to be strengthened, endowed with new abilities, change their appearance to the highest levels of Majesty and helps to uncover the secret history of the Kingdom of Pili. Strategic decisions when forming a party affect battles, requiring you to manage the inertia of the creatures, using skills to win.