Rubicon is trivia you play with friends in the browser. Send a link, they tap it, and you're playing. There's nothing to install. Friends you invite can join that game without an account, and make a free one if they want to keep playing.
Duellum is one on one. Challenge a friend and you both get the same questions at the same moment. Wrong answers cost you health.
Senatus is for a group. Up to eight people sit at one table, joined by a single link, and everyone answers the same question at once. When the round ends you read each other's answers, which is often the best part.
A Russian speaker, a Spaniard and a Finn can share a room. Each gets the question in their own language, on the same clock, and is scored in the language they wrote in. There are 53 to choose from.
Nobody can guess their way to a win. There are no options to pick from, so the scores show who actually knew it. An AI judge reads what everyone meant, typos and all.
Open Rubicon, pick Duellum or Senatus, and send the link, or let friends scan the QR code on your screen. Nobody around? Duel an AI opponent, or play the Daily and compare scores later.
Playing is free, and so is joining any room you're invited to. On the free plan you can start 12 duels and host 3 rooms a day. Citizen, at $6 a month, removes those limits. Full pricing.
The live match against a friend is the same. The difference is the answers: those games give you four options, Rubicon gives you an empty box. How Rubicon compares to other trivia games.