PRACTICE COLLECTION

Track the consequences of a connection

Subtract bridges at both endpoints and remove crossing candidates. Use the resulting limits to explain a new forced connection elsewhere on the board.

Print these three studies with answers

Start with a decision

TRY IT 1 · bridges-remaining-1

Bridge networkB–A: 1 or 2 bridges; B–D: 0 or 1 or 2 bridges; C–B: 0 or 1 or 2 bridges; D–F: 0 or 1 or 2 bridges; E–G: 0 or 1 or 2 bridges; E–A: 0 or 1 or 2 bridges; F–I: 0 or 1 or 2 bridges; G–H: 0 or 1 or 2 bridgesA2B4C1D4E2F4G3H2I2

What can you justify?

What range can the displayed remaining deduction establish for route E–A?

Written explanation

Island A needs 2 individual bridges. Its routes currently allow 1 to 4 in total. Holding the other routes within their limits restricts E–A to 0 or 1. A domain “1 or 2” proves a connection but does not yet choose single or double.

Play the complete starting board →

This question begins at the displayed checkpoint. The full practice link starts at the board’s opening position.

TRY IT 2 · bridges-crossing-1

Bridge networkA–B: 0 or 1 or 2 bridges; B–G: 0 or 1 or 2 bridges; C–A: 1 or 2 bridges; C–D: 1 or 2 bridges; D–G: 0 or 1 or 2 bridges; E–D: 0 or 1 or 2 bridges; F–B: 0 or 1 or 2 bridges; F–E: 0 or 1 or 2 bridgesA2B3C3D5E3F1G3

What can you justify?

What range can the displayed crossing deduction establish for route F–B?

Written explanation

C–D is established with at least one bridge. F–B cross that route between islands, so they must carry zero bridges.

Play the complete starting board →

This question begins at the displayed checkpoint. The full practice link starts at the board’s opening position.

Apply the ideas to a complete board

These are fixed original studies, not new daily puzzles. The three study links below and this collection’s printable pack use identical starting positions. Their checked solution routes are included on each practice page. A collection’s technique drills may also appear in its lessons.

1. Bridges study 4

12 steps in the included checked route. Try the board first, then compare the reasoning.

2. Bridges study 5

14 steps in the included checked route. Try the board first, then compare the reasoning.

3. Bridges study 6

15 steps in the included checked route. Try the board first, then compare the reasoning.

The order uses a repeatable rule trace, not a human difficulty score. A shorter trace is not guaranteed to feel easier. Lights studies are ordered by their construction plans.

Playfield Arcade · Updated 3 October 2026 · AI-assisted writing and code; examples checked against explicit constraints. Our method · Report a correction