Trailhead techniques, easiest to hardest.
In Dayzle the hint and the solver are one engine, so these are the 11 steps it takes to solve a Trailhead board. Open one for a worked example and a clip of the hint teaching it on a real board.
Basic
Count the Prints Basic Find a clearing whose open sides are exactly as many as it still needs. Every one of them is trail.
A clearing shows three paw prints, and one of its four sides is already crossed off. The number is exact, so its three remaining sides must all carry trail.
Check every numbered clearing this way: count the sides already crossed off, and if the sides left open match the number it still needs, there is nothing left to choose.
Follow the Trail Basic Find a marker the trail runs into with only one way out left open. The trail leaves that way.
The trail comes into a marker from the left. The stretches going up and down from it are crossed off, so the only way out is to the right, and the trail goes that way.
Every marker on the loop has trail on exactly two sides, one in and one out. Following the end of the trail like this is the quickest progress on the board, and it often runs several stretches before you have to think again.
All Prints Found Basic Find a clearing that already has as much trail as its prints show. Its other sides are crossed off.
A clearing shows two paw prints and already has trail on its top and left sides. The number is exact, not a minimum, so its bottom and right sides carry no trail. Cross them off.
A crossed-off side tells you as much as a drawn one, and it usually makes the next clearing easy to work out.
Trail Passes Through Basic Find a marker the trail already goes into and out of. Every other stretch touching it is crossed off.
Trail runs into a marker from above and out of it to the right. That marker is finished: a third stretch there would make a fork, and a single loop has no forks. So the stretches to its left and below are crossed off.
No Dead Ends Basic Find a stretch leading to a marker with no other way out. It can't be trail.
A stretch leads to a marker where no trail has arrived yet, and every other stretch at that marker is already crossed off. Trail along it would arrive with nowhere to go and stop dead, and the loop has no ends. So the stretch is crossed off.
This is the mirror of Follow the Trail: one says where the trail must go, this one says where it can't.
Intermediate
No Early Loop Intermediate Find a stretch that would join the two ends of your drawn trail into a small ring. It can't be trail.
You have drawn a trail around three sides of a small patch, and its two ends sit either side of one open stretch. Laying that stretch would seal the trail into a closed ring with the rest of the field left out, and there is only one loop. So the stretch is crossed off.
This one is easy to miss, because nothing nearby looks wrong. The check is always the same: follow the trail from one end of the stretch and see whether you come out at the other.
Corner Clearing Intermediate Find a clearing in a corner of the field showing three prints or one. Its two outside sides are settled together.
A clearing in the top-left corner of the field shows three paw prints. Its two outside sides meet at the corner marker, where nothing else joins them, so the trail takes both or neither. With neither, the clearing would have only two sides left, and it needs three. So both outside sides are trail.
With one print it goes the other way: both outside sides would be two, and it needs one, so neither is trail and its one stretch is one of the two inside sides.
Neighbours Intermediate Find two three-print clearings side by side. The side they share and the far side of each are trail.
Two clearings sit side by side and each shows three paw prints. Leave out the side they share and each needs all three of its other sides, which join into a small closed ring around the pair. So the shared side is trail.
At each end of the shared side the trail can carry on only one way, so each clearing gets only one more side there and needs its far side to reach three. The shared side and both far sides are all trail.
Beside the Forest Intermediate Find a three-print clearing next to a stand of trees. Its other three sides are trail.
A clearing shows three paw prints, and the clearing to its right is forest. The trail never touches a forest, so the side they share is out before you start. That leaves exactly three sides, and the three prints need all of them.
Every clearing next to a forest starts with the side it shares with the forest crossed off.
Corner to Corner Intermediate Find two three-print clearings touching only at a corner. Each uses both of its sides at its far corner.
Two clearings touch at one corner, and each shows three paw prints, so each can skip only one of its four sides. If one of them used both of its sides at the shared corner, the marker at that corner would already have its two stretches, and the other clearing would have to skip both of its sides there, which is one too many.
So each clearing skips one side at the shared corner and uses both sides at its far corner.
Advanced
Inside or Outside Advanced Work out which clearings end up inside the loop and which outside. A stretch between two clearings on different sides is trail.
A finished loop splits the field in two, and every clearing ends up inside it or outside. Crossing a stretch of trail changes sides; crossing a crossed-off stretch does not. The ground past the edge of the field is always outside.
Start from the edge and follow the stretches you have settled. Say they put one clearing inside the loop and the clearing next to it outside: the trail must pass between them, so the stretch they share is trail. If both are on the same side, the stretch between them is crossed off.
