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Ten classic leaves, one ball each. The corner pins are where this gets interesting — your hook stops being an advantage and starts being the problem.
Turn this down for corner pins.
Strikes are what people remember. Spares are what actually move an average. Ten frames of first-ball nine counts with every spare converted scores 190. The same ten frames with no spares scores 90. That gap is the whole game, and it is why serious practice is mostly spare shooting.
The 10 pin is the round most people fail here, and the reason is worth understanding. If you throw a big hook, your ball simply cannot reach the right corner: to arrive out there it has to start further right than the lane allows, and it finds the gutter first.
The fix is what real bowlers do. Drop your revs right down, straighten the ball out, and play it more or less directly. Many league bowlers use a completely different, weaker ball for corner pins for exactly this reason. Try the 10 pin round at 40 rpm and then at 400 rpm; the difference is not subtle.
You will notice there is no 7-10 in the ten rounds. That is deliberate. Real conversions of the 7-10 happen when a pin is driven sideways hard enough to bounce off the pit wall and travel across the deck. This simulation does not model the side walls or pins flying through the air, so in here it is simply impossible rather than merely improbable.
For reference, professionals convert the 7-10 well under one percent of the time. The 4-6, the 4-10 and the Big Four are in similar territory. If those leaves came up, the honest advice would be to knock one down and take the nine.
The score calculator will show you what converting even half your spares does to a game.