The Kretin is an enemy in the game Mario & Luigi: Bowser's Inside Story, which is the main boss fought in the Flab Zone.
The Alpha Kretin appears to be in the shape of a pentagon (or a triangle in later battle). In battle, it will make the separate Beta Kretins either red or green, which the corresponding brother has to attack. It has large legs and arms compared to the Beta Kretin. The Alpha Kretin will create a ball of electrical energy that will move along each of its segments before being launched from the boss's arm cannon. The player can predict which Mario bro the electric spheres will target via the colored Kretin (the electric sphere will target Mario if it lands on the red Kretin, green for Luigi, and blue for both). The energy balls can be destroyed by the Mario Bros hammers.
The Beta Kretin looks similar to a blue orb, with yellow eyes and short feet. In this form, the Beta Kretin does spawn copies of itself with 1 HP.
Mario & Luigi: Bowser's Inside StoryMario and Luigi first meet a tornado of Beta Kretins that kidnaps Princess Peach near the very beginning of the Flab Zone. Mario and Luigi must go through the entire Flab Zone and learn the Spin Jump to get through the area. There are also a few times when Mario and Luigi are close to retrieving Princess Peach from the evil Kretins. When Mario and Luigi are done exploring the area, they trap the Kretins with Peach in one single room where they start to go in battle with Mario and Luigi.
Mario and Luigi save Peach temporarily until Fawful gets back at them.
The Kretin has four phases. It becomes Alpha Kretin in Phase 1. In this form, it is pentagonal, with one Kretin in the centre. It attacks by firing blasts of energy from its arm cannon (can be repelled via hammer.). It can only be damaged if the player smashes the boss's orbs. The red orbs are immune to Luigi's attacks and the green ones are immune to Mario's attacks. Once the orbs are destroyed in their entirety, the Kretin falls apart.
When it enters Phase 2, the Kretin takes on its Beta form. It can create duplicates of itself (Like Dreamy Mario does in his own battle in Mario and Luigi: Dream Team) and the Kretin copies can form a laser relay with their bodies. Mario and Luigi have to jump the laser. After their turn, the Beta Kretin and the duplicates can shuffle around. The fakes have only 1 hit point, the real one takes damage normally and has to be destroyed in order to win the fight.
The third phase plays out like Phase 1 does, but it has a triangular form.
Phase 4 is identical to Phase 2, except the replica laser relay lasts longer.
Once the Alpha Kretin has been destroyed, Class 2 is automatically unlocked in the Challenge Node located deep inside Bowser. In order for Mario and Luigi to participate in Class 2 and fight Alpha Kretin-X, the two must pay a toll of four hundred coins. Once the toll has been paid, the Kretin reappears in its more powerful form, in which the Beta Kretins assume a different appearance, making them look more fierce and solid.
- Alpha Kretin represents AlphaDream's logo. This is possibly based on their logo.
- In the remake, the green Alpha Kretin blobs have surprised expressions, while the blue ones seem to be sleeping.