Mom Piranha is a giant Piranha Plant that appears in Mario & Luigi: Superstar Saga. During the events of the game, it takes up residence in a large egg on the runway at the Beanbean International Airport. She and her offspring take root in the runway, preventing planes from landing or taking off; this also means Princess Peach, who is going to attend an important meeting with Queen Bean and Prince Peasley, is unable to land her plane. Mario and Luigi must get rid of the enemies by having Mario drink water from one of the nearby fountains and spit it on the Piranha offspring, soaking it and making it swell up (also turning it a dull turquoise color). Luigi then has to shock the plant with his Thunderhand. Since the offspring is connected to Mom Piranha, the electricity surges through the roots of the Piranha Plants and into her egg, causing it to crack open, one bit at a time. When the egg is destroyed completely, Mom Piranha is revealed, and interacting with the beast initiates battle.
Mom Piranha is a stubborn foe, but she is fairly easy once the brothers learn her tricks. The enormous plant is always protected by two Piranha Plants, who act as distractions and extra attacks for the boss. If the plants are destroyed, Mom Piranha will create new ones. The colors also follow a mechanic: for each Piranha Plant on the field that is the same color as Mom Piranha, she will heal 10 HP. Mom Piranha is vulnerable to Hand attacks. If she is red, Thunderhand is effective, Firebrand if she is blue. However, the opposite element will heal her, and the Piranha Plants are granted extra attacks if their leader is wounded. Mom Piranha is extremely resistant to jump attacks, but takes normal damage from hammer attacks. She also has two attacks herself: She will spit a blue ball that must be hammered back and will damage all enemies if successfully countered (this will heal Mom Piranha even if it hits her), or she will swipe with one of her tentacles. The tentacle sweeps back and forth and must be jumped over twice (this will heal her even if dodged every time).
Upon victory, the Piranhas stop spawning, and the Princess and her entourage finally land on the royal jet.
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