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Manticores are massive Grimm resembling black lions. They have white bone-like spikes and spines covering their bodies, including a series of protruding spikes forming a "mane" around their heads. They also possess large pairs of bird-like wings covered in black feathers. They have scorpion-like tails, which end in a white bone-like venomous stinger.
In the episode "Argus Limited", the newly reformed Team RWBY, along with Qrow Branwen, Oscar Pine/Professor Ozpin, Jaune Arc, Nora Valkyrie, and Lie Ren board the Argus Limited train through Anima to Atlas in order to deliver the Relic of Knowledge there and search for the next one. However, during their trip, the train is suddenly attacked by a swarm of Manticores and a Sphinx.
The two Huntsmen named Dee and Dudley go on top of the train to fight off the threat, but Dee is quickly killed by a charging Manticore. Qrow and Team RWBY step in to help, holding off the Manticore swarm while Dudley rushes to activate the train's turret defenses. These hold off the Manticore swarm until the Sphinx Grimm signals for them to take the turrets out, simultaneously bringing them over to the inhabited section of the train. Qrow fends off more Manticores and tells Oscar to tell Dudley to shut off the turrets. However, Dudley sees the turrets killing Manticores and refuses. The train enters a tunnel, giving the fighters a brief intermission before the Grimm swarm the train again.
Team RWBY manages to convince Dudley to turn off the turrets so that they may lure the Grimm to the back of the train. Once there, Ren can use his Sembalnce (amplified by Jaune's) to mask the negative emotions of the passengers. Team RWBY and Qrow would then detach the inhabited part of the train from the back, allowing the passengers to get to safety and allowing them to meet in Atlas later.
The train exists the tunnel and Qrow and Team RWBY begin fighting the Manticores and Sphinx again, this time pushing them to the back of the train. Ren uses his Semblance, hiding the train from the Grimm's view and allowing it to escape. A Mandicore attacks Oscar, but he gives Ozpin control so that Ozpin can fight it off with his cane. Team RWBY then works together to simultaneously beat and dismember the swarm of Manticores, picking them off individually until only the Sphinx remains, which they all need to team up to defeat. They succeed, but the Sphinx launches one final attack before dying that destroys a part of the train tracks and derails the train, leaving Team RWBY, Qrow, Oscar/Ozpin, and a mysterious old woman named Maria Calavera.
In "Seeing Red", Argus is attacked by a swarm of Manticores, Sphinxes, and a Leviathan.
In "Our Way", the Atlas military fights off the Sphinxes and Manticores while the Beacon students and Caroline Cordovin fight off the Leviathan. After it is defeated, Cordovin tells them that the Atlas military will take care off the remaining Grimm, saving Argus.
Powers and Abilities
Manticores are covered in armor plating and spikes, allowing for great durability and defense. They can curl up into balls and spin, using their spikes as weapons. They can also fly using their massive avian wings, and are shown to be quite agile in the air. They possess large claws and teeth, which they use to slash and bite at victims. Manticores also have long tails ending with scorpion stingers, which feature long, deadly barbs and are most likely venomous. Manticores are also capable of launching flame projectiles from their mouths, which deal great damage and have considerable range.