REIGN is a Tabletop Roleplaying game written by Greg Stolze that uses the One-Roll-Engine, which is used in other games Godlike, TabletopGame/WildTalents, and Nemesis.
!!REIGN and its supplements contain examples of:
* FighterMageThief: Although the game is classless, directly referenced in the default setting.
---> Magic splinters numbers. Stealth destroys magic. Numbers overwhelm stealth.
* HonorBeforeReason: Dindivaran nobles are defined by this trope.
* OurDemonsAreDifferent: They're powerful, magical, and bizarre, but entirely earthly and natural creatures with no ties to souls or the afterlife. Demon eggs form in the soil naturally, although the exact mechanism and cause isn't clear.
* OurMonstersAreWeird: The game has giant fleas made of earthen materials which are known for crushing entire cities by landing on them after jumping. Also for being full of precious metal and gems it sucks out of the ground... and demons, because it also sucks their eggs out of the ground.
* PointBuildSystem: REIGN actually uses three: One for creating your character, one for advancing your character, and one for creating a Company.
* PoorCommunicationKills: Checking that your company of mercenaries all know the ''same'' military hand signals, not just that they know them at all turns out to be kind of important in one fluff aside.
* SpellCrafting: The first supplement includes an exhaustive guide on how to create new magic spells and schools, and encourages players and Game Masters to make their own.