Rat Defense Swallowstail Mate in Chess

In the Rat Defense, a “swallowstail mate” is a specific mate pattern where the defender’s king is funneled into a tight square cluster and the attacker converts a forcing sequence into a final net. The defining feature is a lure/deflection that makes the king’s escape squares overlap with the attacker’s controlling pieces, so the last move delivers mate rather than a mere win of material.