Leo differs from Mothra as he is commonly labelled as a male. Plus, unlike Mothra who is usually portrayed as being concerned more for the plights of her homeland and people, Leo takes on a more active role as a protector of the Earth, as well as taking on a Gamera-like affection for children.
Leo first appeared as an egg layed by an aged and weakened Mothra in 1996. He hatched prematurely during a battle between his mother and a monster called Desghidorah and, despite being hopelessly outmatched in his larval form, attacked his mother's aggressor. After a long battle, the two managed to escape, though by that point, Mothra had been badly wounded, and she collapsed into the sea. Despite his best attempts to help her, Leo could do nothing as he watched his mother sink into the depths. Leo then retreated to a remote island where he cocooned himself against a 10,000 year old tree. After some time, Leo emerged as a swarm of multicolored butterflies which merged into one giant insect. Leo then flew to Hokkaido to do battle with Desghidorah, and arrived in a flurry of laser and energy beams. The demonic dragon could not stand against the power of the new Mothra and was soon defeated. With the help of the Seal of Elias, Leo imprisoned the beast once again within its ancient tomb. Leo then went on to replenish the land destroyed by Desghidorah, releasing a powder that sped up the growth of Hokkaido's flora. With the forests and fields returned to their original beauty, Leo returned to Infant island.Dagahra began infesting the ocean with toxic parasites called Barems. Leo attacked Dagahra and seemed to have the upper hand, until the battle was taken underwater. Unable to combat Dagahra in his element, Leo was overwhelmed by a swarm of Barem and awaited his opponents' killing blow. However, with the assistance of the Elias, Mothra Leo was replenished by the water spirit Ghogo and was transformed into a new form, Rainbow Mothra (レインボーモスラ?, Reinbō Mosura). Suffused with the water spirit's ancient magic, Rainbow Mothra re-entered the fray, relentlessly assaulting Dagahra. Yet, when the toxic one retreated below the waves, Rainbow Mothra followed suit and dove under the water, transforming himself into his new aqua form, Aqua Mothra (アクアモスラ?, Akua Mosura), and finishing off Dagahra. With his foe defeated, Rainbow Mothra then flew off into the horizon and thus, the world is once again safe. Grand King Ghidorah when he was eating humans. The two fought, but Rainbow Mothra was quickly defeated. Rainbow Mothra was transformed into LightSpeed Mothra and went back in time to kill Grand King Ghidorah when he was weaker. He went back to the Cretaceous period, where he fought Cretaceous King Ghidorah. He defeated Cretaceous Ghidorah, but his tail was buried in the ground. Cretaceous Ghidorah regrew from the tail, and arrived in the present only a day later. He attacked Grand King Ghidorah as Armor Mothra (鎧モスラ?), and killed him. Armor Mothra transformed into Eternal Mothra and flew away in peace.
- Mothra Leo can spray web out of his mouth with a multicolored electrical aftershock.
- Mothra Leo can fire a Mega Breast Cannon from its chest.
- Mothra Leo is able to become invisible.
- Mothra Leo can move at 40 kilometers per hour.
- Mothra Leo flies at the speed of mach 15.5.
- Mothra Leo fires three multicolored Cross Heat Laser beams from his forehead.
- Mothra Leo unleashes Jade Bolts fire from his wings.
- Mothra Leo fires a Mega Breast Cannon from chest.
- Mothra Leo able to break apart into billions of smaller 30.5cm Mothras.
- Mothra Leo can perform an Excel Pileload by flying straight up and spinning to release several jade rings from his body.
- Mothra Leo is able to release Reflective Green Powder from his wings which can weaken and cause pain to his opponent.
- Mothra Leo can do a Sparkling PryeRoad, a series of cascading shafts of blue energy that can split the earth as bolts flicker across his wings.
- Mothra Leo can perform an Excel Dash by charging itself with energy and flying at mach 85 for up to 65 seconds.
- Mothra Leo is able to perform a Sun Strike Buster by raining down powder in a circle, and then from the center of the circle, a giant beam of blistering emerald energy will burst forth from the sky.
- Mothra Leo is able to speed the growing process of plants.
- Rainbow Mothra fires a Cross Heat Laser beams from his forehead.
- Rainbow Mothra fires a breast cannon.
- Rainbow Mothra emits energy bolts from his wings.
- Rainbow Mothra fires a Mega Breast Cannon from his chest.
- Rainbow Mothra flies at the speed of mach 15.
- Rainbow Mothra emits a reflective green powder from his wings.
- Rainbow Mothra emits a pressure field.
- Rainbow Mothra emits a levitation field.
- Rainbow Mothra fires a beam pulser.
- Rainbow Mothra emits a sparkling pileload rainbow.
- Rainbow Mothra fires rainbow buster.
- Rainbow Mothra can transform into Aqua Mothra.
- Aqua Mothra fires a Cross-heat pulser beam.
- Aqua Mothra swims up to 200 knots.
- Aqua Mothra enables flight.
- Aqua Mothra emits an Illusion Mirage.
- Aqua Mothra emits a Sparkling Pileload Rainbow.
- Aqua Mothra fires a Cresent Dash Beam from his antennae.
- Aqua Mothra emits a Pressure Field.
- Aqua Mothra can transform into either Rainbow Mothra or LightSpeed Mothra.
Light Speed Mothra
- Light Speed Mothra can fly at a speed of 186,000 miles per second.
- Light Speed Mothra is able to travel through time.
- Light Speed Mothra can change back into Rainbow Mothra.
- Armor Mothra flies at the speed of mach 15.
- Armor Mothra has a thick armor that protects him from any energy/beam attacks.
- Armor Mothra uses razor sharp wings.
- Armor Mothra fires an Armor Cross Heat Laser.
- Armor Mothra has an Armor Wing Cutter.
- Armor Mothra emits an Excel Dash Buster.
- Armor Mothra can transform into Eternal Mothra.