- "Prototype skin? With color green? I'll take it."
- —Mantis choosing his plane skin
Olivier "Mantis" Perrin, callsign Mantis. Veteran of the Continental War, He served with distinction during the Battle of San Salvacion, defending the retreating Erusean forces from the ISAF offensive until he was captured and released after the war. Olivier later served from 2008 to 2017 as a test pilot for EASA, obtaining extensive knowledge on aerodynamics, jet propulsion technologies, rocketry and other sciences. He helped test several types of experimental aircraft. His accomplishments earned him the position as an astronaut, albeit for a very short time, testing manned SSTO craft and conventional rocket capsules sent into orbit by EASA. He was also one of the pilots in charge of testing the development and deployment of experimental aircraft modification such as various types of stealth coatings, ECM suites as well as directed-energy and electromagnetically propelled weaponry. He was also involved in the initial testing of what would become the X-02S Strike Wyvern, though the shift of the Erusean Air Force away from manned fighers and towards the development of UAV technology and artificial intelligence meant downsizing the test programs, so he was no longer needed. In order to keep flying, Olivier asked to be transfered to a conventional fighter squadron, where his leadership skills and knowledge were greatly appreciated.
During the Lighthouse War, Erusea seized Tyler Island, using its mass driver to ressuply the Arsenal Birds and deploy new weaponry, such as the Helios missiles. Due to his previous experience, Olivier was assigned to the Tyler Island Space Center, supervising operations and coordinating the squadrons based at the island.
Due to its strategic importance, Osean forces trying to seize the island as early as August, with multiple hit-and-run raids and bombings from Osea as they attempted to chip away at the defenses to prepare for a landing operation, to which Olivier and his squadrons responded with effective counterattacks. The loss of the Arsenal Bird "Liberty" on August 19 shrunk the effective area of their air defense zone enough for Osea to start a massive landing operation on the island, managing to establish a foothold on the island. The situation reached a stalemate, which was only broken by the loss of communication satellites, but this only worsened the situation. Lack of orders from HQ meant disagreements among Erusean forces on how to proceed. These disagreements escalated into all out fighting. Forces that aligned themselves with the Radicals seized the space center by force, recognizing its strategic importance in keeping the remaining Arsenal Bird up and running. Olivier refused to take part in the insurrection and managed to escape to the mainland. The situation turned from bad to worse as anarchy reigned in the island. Atrocities were committed in the island against civilian population, mostly of Belkan heritage, scapegoating them for the situation.
A counterattack operation was hastily organized by the Conservative faction, with a ground attempt at taking back the Space Center to prevent the Arsenal Bird from being ressuplied, taking advantage of the Osean rout as they hastily attempted to leave the island. When this failed, "Operation No Return" was initiated, consisting of a large scale carpet bombing operation to destroy the Radical forces, to prevent them from using the mass driver to resupply the Arsenal Bird and destroy the remaining retreating Osean forces still on the island. Olivier was one of the escort fighters of the bomber squadron. He was well aware that the operation would inflict a large amount of collateral damage, including Conservative troops and civilian casualties, but participated in the operation based on simple, albeit cold calculations: allowing the Radicals to ressuply the Arsenal Bird would prolong the war and result on more casualties for all sides and civilians in the long run.
The bombers were stopped by fighters of the Osean LRSSG and shot down before any bombs could be dropped, though. Olivier attempted to fight back, but was shot down by Trigger over waters close to the Space Center. His fighter caught fire in the attack, but he managed to eject and was found in the water shortly after by a retreating Osean vessel, his life was in danger at the time, the crew onboard was deciding should they kill him, but luckily for him, they decided let Olivier to live. They treated his wounds, which included some burns caused by the fire and injuries to his limbs during the rough landing. While being held prisoner by the Oseans, he chose to cooperate with them, explaining his situation, the situation of his squadron and his faction and their desire to end the war. He also gave detailed information about the way the Eruseans had been using the Arsenal Bird and everything he knew about its technology. This information proved valuable for the coalition formed a few weeks later in the attempt to bring down the Arsenal Bird, Despite his injuries, he still cooperate the coalition during Operation Daredevil. After the war he was investigated for his possible involvement with war crimes on Tyler island, but he was cleared of any wrongdoing as no evidence linking him to the atrocities was found.
He retired from the Erusean military, having seen enough of war for an entire lifetime in just a few weeks. Today he lives a quiet life with his wife and children in a ranch north of Sierraplata, still complaining about Trigger beating his record for the fastest pilot flying along the mass driver.