There is nothing more clichéd in fantasy games than the fabled first adventure (where the players meet each other for the first time and go out on an adventure). Since Risus is all about clichés, it seemed fitting to have a first adventure of sorts here.
The PCs are living in a fairly small town along a major trade route. There have been reports of smaller caravans not making it to their destination. It appears as if someone is raiding the caravans and leaving no survivors.
If you want to really stick to fantasy adventure cliché, you will have all of the players in a tavern where they are asked for help...otherwise, you could just have them all hired individually by a concerned citizen. The second option may be more fun because it will give the GM more ways to motivate the players than altruism.
In either case, what should happen if the adventure is to continue is that the PCs are either hired to go along with the next caravan to help protect it from a raid, or the PCs are hired to find out what happened to the last caravan that wasn't heard from.
The hiring of the players can server as an introduction to non-physical combat in Risus as they negotiate their contract. Pit them against Thomas Shieldstone [wily merchant (4), town mayor (4)].
What's Going On
A band of [insert evil group or race here] has been raiding the caravans. So far, they've been targeting the smaller caravans in a very systematic and organized manner. The attacks usually take place as the caravan is either making or breaking camp. There hasn't been a consistent location for the attacks, so whoever is attacking the caravan is probably pretty mobile.
What the PCs Must Do
If the PCs were along for the ride as hired muscle for the caravan, they must help protect the caravan from attack ([insert evil group or race here] Raiding Party (7d8)). If they fail to protect the caravan, then they can follow the same path as the PCs who are investigating the attacks (i.e. track down the raiders). If they succeed, they can follow any fleeing raiders back to their camp.
The raiders use a small collection of tents to move their base of operations around; so finding them is the first challenge. This will give wilderness type of players a chance to try out their clichés, and you can have a few not-so-random encounters along the way to get everyone used to Risus combat.
Eventually, the PCs will find the raider's given camp of the day. If the PCs are clever, they can formulate a plan of attack to overcome the raiders ( [insert evil group or race here] Raiding Party (7d8 (feel free to adjust this if the players fought and killed off some of the raiders previously)); semi-domesticated wolves (3) act as sentries and howl at any approach; the raiders regularly make use of large fires as well to help keep anyone from sneaking up on them).
Assuming that the PCs defeat the raiders, have them find an interesting map to tempt them to continue on to the next adventure.