Leonin

Leonin are lion and tiger-like humanoids from a distant star and part of the colloquially named "Hunter Races." The Leonin are known for their physical and mental strength, having a culture that focuses on teaching Leonin to find their own moral standards and follow them closely. Their extreme traditional following of their ideals often lead them to become Paladins, but their history as a race of combat leads many towards violence. As one of The Hunter Races, they're often prized as ship crew members and mercenaries and famous for their durability and devotion.
As the Hunter Race with the longest lasting empire, they are also the only one with a persistent language that is spoken past their race in the modern day.

Leonin Oath Culture

Leonins are asked when youth to explore the world and then decide their core tennets, usually a list anywhere from 4 to 10 core beliefs. These beliefs are incredibly important in their culture: making an oath choice too early marks you as immature in their society, making one too late makes you too worldly. Making oaths makes you connected to something bigger, and Leonin take it very seriously.
Leonin culture has laws surrounding the breaking of oaths that transcend planetary law and become almost religious in nature. An accusation of oath breaking could get the accuser killed if false, but could ruin the Leonin's life if true.
Oaths can be changed as you age, though it's not incredibly common, as usually Leonin instead bend the logic of their oaths to fit their aging mentalities. Changing oaths is an intense process that is deeply cultural and something entirely forbidden outside of the presence of one in power, all of your children and/or your spouse, and within a personal meal. Usually, in old Leonin culture, these would be finished with a blood tie.

DND Mechanics

• Ability Score Increase. Your Constitution score increases by 2, and your Strength score increases by 1.
• Age. Leonin mature and age at about the same rate as Humans.
• Alignment. Leonin are prideful, and tend toward lawful alignments.
• Size. Leonin are typically over 6 feet tall, with some standing over 7 feet. Your size is Medium.
• Speed. Your base walking speed is 35 feet.
• Darkvision. You can see in dim light within 60 feet of you as if it were bright light and in darkness as if it were dim light. You can’t discern color in darkness, only shades of gray.
• Physical Prowess. You have resistance to non-magical slashing, piercing, and bludgeoning damage.
• Claws. Your claws are natural weapons, which you can use to make unarmed strikes. If you hit with them, you can deal slashing damage equal to 1d4 + your Strength modifier.
• Daunting Roar. As a bonus action, you can let out an especially menacing roar. Creatures of your choice within 10 feet of you that can hear you must succeed on a Wisdom saving throw or become frightened of you until the end of your next turn. The DC of the save equals 8 + your proficiency bonus + your Constitution modifier. Once you use this trait, you can't use it again until you finish a short or long rest.
• Languages. You can speak, read, and write Common and Leonin.