In UFO 50, the characters Amy and Alpha are the same person.

Amy traps her little sister in the back room so she can throw a party (Party House + Mini & Max). Mini helps the Mol Duk civilization of mold-people, and hears their prophecy that they'll become a technologically advanced people (Mini & Max). An unnamed friend of Amy gets kidnapped by a man who has become an infested mold zombie after drinking Mol Duk tea (Night Manor) given to him by a therapist (probably one of the counselors from Party House). Amy and friends fight a zombie apocalypse, get abducted by aliens, beat up the aliens, and continue their journey, presumably keeping the flying saucer (Fist Hell). The Mol Duk people become Woogie's species (Onion Delivery; yes it was Earth all along). Amy escapes the planet using the space ship, then goes on a series of adventures under a new assumed name, Alpha (Velgress, Overbold, Pingolf, Quibble Race). Further evidence for this is that both Amy and Alpha have wildly inconsistent hair color from game to game.