Your longboat rows down a river between rocky headlands. The first boat past the last headland and over the finish line wins. Nothing is hidden and nothing is rolled: every boat can see exactly what every other boat can do.
The oars along the bottom of your boat's card are your crew's fresh oars. Every stroke spends some and then the crew gets a breather, so a hard stroke leaves you slower for the next few turns. There are four strokes:
You always have Glide, even with no oars left, and it fills the crew back up fastest. Rowing steadily is the pace you can keep up all day; driving and sprinting are what you spend to win a position.
At a headland the river bends, and the inside of a bend is shorter. Rounding a point costs 2 lengths on the inside lane, 3 one lane out, and 4 from the far shore. The points swap shores down the course, so you are always crossing to set up the next one. Only one boat fits in each patch of water, so the inside line can be taken before you get there.
Sitting one or two lengths directly behind another boat in the same lane puts you in its wash: your stroke reaches one length further and costs one oar less. Leading is hard work, and a boat that has dropped back can save its crew by tucking in behind somebody.
If a stroke runs into a boat ahead in your lane with power to spare, the oars clash: both crews lose 2 oars, your own crew gets no breather that turn, and the boat in front is shoved out of its lane: off the inside line, if there is a point coming up. Ease off to a gentler stroke and you will simply pull up behind them instead. Barging is a weapon, but it costs you as much as it costs them.
Once a race your drummer can call for a big effort: +2 lengths on that stroke, for free. Spend it to steal the inside line, to break a slipstream, or on the run to the finish.
When a boat crosses the line the round is played out, so every crew has rowed the same number of strokes. The boat that carried furthest past the line wins. If two boats are level, it goes to the one with more oars still in hand; still level, and the win is shared.