In the finale of High School DxD BorN, Rias used an armor variant, presumably similar to Crimson Extinct Dragonar, after being manipulated by Issei's evil double. Gorou Hyoudou • Miki Hyoudou • Juzo Hyoudou • Mil-tan • Kiyome Abe • Freed Sellzen • Walburga • Valper Galilei • Shooting Star • Elaine Westcott • Uther Pendragon • Magnus Rose • Meredith Ordinton • Kuoh Academy Students • Belzard • Elsha • Yukihiko Hoderi • Aika Kiryuu Now my adorable servants! Let's blow away the enemy before us as the Gremory group!" (Volume 12, Life -2) Great Demonic Power: Like Sirzechs, Rias inherited exceptional demonic power from her parents and has great talent and skill in using it, even by the standards of a High-Class Devil. After Issei transferred power to her, her demonic power increased to where it rivaled an Ultimate-Class Devil, shaking the ground, and being able to mildly injure the Cadre Kokabiel. Azazel noted that even without training, Rias has the potential to become one of the highest class devils using natural talent. [3] Rias has further improved her demonic power through dedicated training. She was capable of overpowering Ultimate-Class Devils wounded by Crom Cruach, [4] and while in her Balor Princess Form could keep up with Fenrir at 80% percent power. [5] Rassei • Samael • Issei Hyoudou • Tannin • Bova Tannin • Blizzard Dragon • Sprite Dragon • Earth Dragon • Spectre Dragons

Ishibumi describes Rias as being the King, the mother, and the big sister of her peerage all at once. Oppai Beam (おっぱいビーム, Oppai Bīmu): Rias has gained the ability to project a red light from her breasts, which recharges Issei's energy. Each use of this power causes her breasts to temporarily shrink in size, however, her breast size will restore itself after a few days of rest. Rias was one of the young Devil heirs and Kings chosen to compete in the Youth Devil Rating Game Tournament. Rias was decided not to have large breasts originally, as Ishibumi said he intended Rias' sizes to be only a bit larger than the common girls in Japan would have. However, he inspected Miyama's illustration of her with big breasts, he fell in love with it, and decided to give her large breasts. Rias loves participating in Rating Games, as she dreams of becoming the Rating Game champion by defeating the current Rating Game champion; Diehauser Belial, with the help of her peerage. While Rias is a powerful devil in her own right, being much stronger than average High-class Devils and according to Azazel, being able to become a Ultimate-class Devil just on the virtue on her talent alone, Rias suffers a bit of an inferiority complex when she compares herself to her fellow Rookies Four colleagues, as she feels inferior to Sona as a strategist and that she is far weaker in power than Sairaorg. However, according to Riser and Azazel, Rias has a talent for finding and recruiting talented individuals for her peerage, inspiring great loyalty and growing stronger with them as seen in her meeting with Issei. During the Azazel Cup, she was highly evaluated as a scout as she managed to recruit Crom Cruach and Vasco Strada along with 2 Longinus possessors, being praised by the professional critics. She is noted to be a skilled negotiator, as she was able to convince Rossweisse to join her peerage by offering her better working conditions and a better salary compared to her previous job in Valhalla, and while during the Azazel Cup, she was able to convince Vasco Strada to join her team after he declined all prior invitations to participate in the Cup by appealing to his warrior swordsman spirit and offering to restore his youth without using a Devils ability, thus not violating his faith with Strada praising her negotiating skill as a sweet Devil's whisper.

Due to being taught about Japan from Souji Okita, Rias has developed an obsession with Japan, buying various Japanese souvenirs and being ecstatic while visiting Kyoto during her school field trip, though she became pouty and stomped at the train station due to being unable to fully explore Kyoto. She is the first to become Issei's girlfriend, as well as becoming the first to become engaged to him. [18] Rias has stated wanted to have one daughter with Issei but she strongly predicted that their first child will be a boy. [19] Introducing herself to Issei) " My name is Rias Gremory. I am a Devil. And I am your Master. Nice to meet you, Hyoudou Issei-kun. Can I call you Ise?" (Volume 1, Life 1)

Defense: Rias can create several barriers able to protect herself and her servant, such as from Katerea's self-destruction spell during the Three Factions Conference. Rias is competitive and hates to lose, especially after losing her first Rating Game against Riser as she strives to always win, whether it is in sports or Rating Games.Rias has a driving license and owns multiple cars such as a red saloon and a red convertible being two of them. [15]

Memory Alteration: Rias has shown that she has skill in memory alteration, using it on Issei's parents. Enku • Viser • Regulus • Tannin • Souji Okita • Surtr Second • MacGregor Mathers • Beowulf • Isabela • Ile and Nel • Karlamine • Mira • Siris • Xuelan • Yubelluna • Bülent • Marion • Rudiger RosenkreutzSuzaku Himejima • Shuri Himejima • Suou Himejima • Akeno Himejima • Tobio Ikuse • Ouryuu Nakiri • Nakagami Nakiri • Momiji Nakiri • Genbu Doumon • Seiryuu Kushihashi Prior to the series, Rias has reincarnated Akeno Himejima, Koneko Toujou, Yuuto Kiba, and Gasper Vladi as members of her peerage. Rias met Akeno, her Queen, first servant, and best friend, in Japan, saving Akeno from being killed by her fellow Himejima Clan members after Akeno accidentally entered Heinrich Cornelius Agrippa's territory. She then met Koneko, her second servant, after her brother rescued Koneko from being executed, leaving Koneko under Rias' care. She later reincarnated both Yuuto and Gasper, the former who died after being a part of the "Holy Sword Project" and the latter killed by Vampire hunters.

Crimson Extinct Dragonar ( 深紅の滅殺龍姫 ( クリムゾン・エクスティンクト・ドラグナー ), Kurimuzon Ekusutinkuto Doragunā): Also known as Crimson Dragon Princess of Annihilation. A combination technique between Rias and Issei, where he uses his Red Wyverns and they sync both of their auras and the Wyverns attach themselves to Rias to create her own female version of Issei’s Scale Mail. The armor acts just like Issei's, boosting Rias' abilities and giving her the ability to utilize Boost, Transfer, and Penetrate until she reaches her limit. Galatine II( ガラチン II, Garachin II) : A crimson sword able to be used by a devil, which Rias had received from Heaven as a blessing after her engagement to Issei. She plans to pass it on to their future children. She is proud of her family's name, but she does not like being seen as Rias of the Gremory Family. The reason for her living in the human world (as revealed in Volume 2 of the novels) is because there, everyone sees her as Rias, not as a Devil or as the Crimson-Haired Ruin Princess. Due to this and the fact that the only men who showed interest in her were interested in her due to being the Heiress of the House of Gremory, Rias soured on the idea of finding a lover, until meeting and falling in love with Issei. Expert Tactician: Though outsmarted several times throughout the series, Rias has proven herself to be an excellent tactician and has saved her team along with others many times due to her profound intellect and her ability to handle unexpected difficulties calmly. Transformation: In True Volume 3, she can use her demonic power to change the color of her hair from crimson to blonde.Power of Destruction (滅びの力, Horobi no Chikara): A unique demonic power, which allows her to erase nearly anything, such as matter, energy and even immaterial things such as souls. She would originally often release massive blasts to engulf and erase her targets, but Rias has improved her control over her Power of Destruction to the point of being able to compress it into softball-sized bullets and release them in quantities Kiba compared to a machine gun, which he noted that those without enough power would vanish from one of them. Dulio Gesualdo • Griselda Quarta • Irina Shidou • Diethelm Waldseemüller • Kiyotora Shinra • Nero Raimondi • Mirana Shatarova • Ryuu Heikan • Jessica Lagerkvist • Caesar Villiers • Lint Sellzen