From the Super Mario Wiki
Red Magikoopas (abbreviated as R Magikoopa in Paper Mario and R. Magikoopa in the sequel) are red-robed Magikoopas that primarily appear in the Mario role-playing games, their behavior varying between series.
Super Mario RPG: Legend of the Seven Stars
In Super Mario RPG: Legend of the Seven Stars, a Magikoopa, after being brainwashed by Smithy, dons red robes. After he is defeated in combat by Mario and his allies, the Magikoopa's red robes turn back to blue.
Paper Mario series
In the Paper Mario series, Red Magikoopas use attack-increasing spells for its allies in battle. In addition to wearing red robes, they are depicted having green shoes with green jewels for their magic wands.
In Paper Mario, they are encountered later in the game and never appear outside of battle. In battle, they can boost another enemy's ATK by one point, but otherwise fire a magic blast or strike Mario with its magic wand, both attacks dealing three points of damage. Sometimes Red Magikoopas will ride brooms, but this doesn't affect their stats in any way, except hammer attacks will miss. When alone, it flees from battle.
In Paper Mario: The Thousand-Year Door, one Red Magikoopa appears as an enemy in the Glitz Pit, and member of the Magikoopa Masters. In this game, it has gained the ability to raise its allies' defense, as well as their attack power. Additionally, it can now clone itself if alone.
Mario Sports series
Mario & Luigi series
Mario & Luigi: Dream Team
In Mario & Luigi: Dream Team, Kamek creates a red-robed clone of himself called Kamek (Red) to assist him in his third battle against the Mario Bros. in Dreamy Neo Bowser Castle. This clone does not raise stats like its other fellow clones or even like Red Magikoopas in the Paper Mario series. Instead, it will attack on its own by summoning a giant broom to sweep Mario up.
Mario & Luigi: Superstar Saga + Bowser's Minions
Red Magikoopas appear in Mario & Luigi: Superstar Saga + Bowser's Minions after being absent in the original game. They are labeled as Magikoopa (Red). They appear as enemies and recruitable allies exclusively in Minion Quest: The Search for Bowser. They are ranged troopers, and can use their magic wands to raise the unit's power. Like other Magikoopas, they are weak against Bowser Jr.
Mario & Luigi: Bowser's Inside Story + Bowser Jr.'s Journey
Red Magikoopas also reappear in Mario & Luigi: Bowser's Inside Story + Bowser Jr.'s Journey as enemies and allies in Bowser Jr.'s Journey mode.
Puzzle & Dragons: Super Mario Bros. Edition
As an enemy, a Red Magikoopa attacks by firing a blast of fire magic at the screen, inflicting Fire damage to the player's team. Their Skill, Fire Trick, changes all Water and Heart Orbs on the Orb field into Fire Orbs. When defeated, it may occasionally drop a large Coin worth 100 coins or a Grand Fire Block of itself. It will always drop a Spiky Shell when defeated with a 10+ Combo attack.
Red Magikoopas can be found in World 8- (appearing rarely in the last regular battle), World 8- (as part of the boss battle with the four other Magikoopa types), and World 8-. Because Red Magikoopas occasionally drop Grand Fire Blocks in addition to appearing only in static enemy formations in the latter two courses, and within a rare enemy formation in World 8-Tower 1, they are one of the most difficult enemies to recruit in the game.
As teammates, Red Magikoopas have an HP rating of 5/6, an ATK rating of 5/6, and a RCV rating of 0/6. Their Max Lv. is 99. Their Fire Trick Skill functions the same as it does when they appear as enemies. Red Magikoopas use Spiky Shells and Grand Spiky Shells to raise their Skill levels. Red Magikoopas may give ATK+ bonuses to other teammates when being depowered. Their Awoken Skill, Skill Boost, reduces the amount of turns required to first use Skills when entering a course.
In version 2.0 of Puzzle & Dragons: Super Mario Bros. Edition, the player can transform a Red Magikoopa into three other forms in which another Magikoopa accompanies it: Red Magikoopas, Red/Green Magikoopas, and Red/Purple Magikoopas. All three forms share the same Skill and Skill Item requirements, and have an HP rating of 5/6, an ATK rating of 5/6, and a RCV rating of 0/6 (with the exception of Red/Purple Magikoopas, which has an RCV rating of 1/6).
Red Magikoopas can be created by transforming a Red Magikoopa with six Fire Flowers. This duo is a Fire/Fire attribute teammate, and its Awoken Skill, Fire Boost, raises ATK of the player's Fire attribute teammates when they clear a horizontal line of Fire Orbs.
Red/Green Magikoopas can be created by transforming a Red Magikoopa with six Super Leaves. This duo is a Fire/Wood attribute teammate, and its Awoken Skill, Twin Target, raises ATK and attacks two foes for each of this ally's attributes that the player clears four Orbs for.
Red/Purple Magikoopas can be created by transforming a Red Magikoopa with six Boo Mushrooms. This duo is a Fire/Dark attribute teammate, and shares the same Awoken Skill as Red/Green Magikoopas.
Profiles and statistics
Paper Mario series
Paper Mario: The Thousand-Year Door
Mario & Luigi series
Mario & Luigi: Superstar Saga + Bowser's Minions / Mario & Luigi: Bowser's Inside Story + Bowser Jr.'s Journey
Names in other languages