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Tap an arrow with a clear exit lane to send it off the board.

@ SIGN SPECIAL BOARD

C15 @ Sign is shaped like the email "@" symbol. Its spiral loop creates a continuous dependency chain from the outer swoop to the inner letter "a".

At-Sign Level (C15): Board Solution & Analysis

The internet "@" symbol rendered in winding arrow polylines.

Board Specifications

Attribute Specification Strategic Note
Arrow Count 72 arrows Requires structured perimeter sweeps
Grid Dimensions 42×42 Compact tight grid
Opening Free Exits 11 arrows (15.2%) Immediately playable on turn 1
Solvability Status 100% Machine Verified Every stuck position is a reading error

Opening Strategy & Walkthrough

1. Initial Border Sweep

Unwind the outer tail swoop on the bottom-right before attempting the inner "a" loop.

2. Key Blocker Obstacle

The inner "a" loop is completely trapped until the outer "@" tail is unwound.

3. General Arrow Logic Rule

An arrow leaves the board only when every cell between its head and the outer edge is clear of non-removed arrows. Removing one arrow unlocks the lanes behind it.

Frequently Asked Questions

What is the strategy for @ Sign level?

Unwind outside-in following the spiral tail.