Triple look-ahead
Try one animal in a cell and follow the forced moves along that line. If they collide with a rule, the cell is the other animal.
Pip: Suppose cell 2 is an owl: cell 3 becomes a fox (bookends), then cells 3–4 are foxes with cell 5 forced… follow the chain. It breaks, so cell 2 is a fox.
Interactive example · 1 of 1 · tap the empty cells
Why it works
Look-ahead is still local to a single line, so it stays quick. The app's hints will name it when it's the cheapest move available; on the harder tiers it appears constantly.
Try it
Today's Daily is the same puzzle as the app. Unlimited practice is one click away.