Tripping the knight fantastic

Intro

K+3N can usually overwhelm K+N, unless a trade of knights can be forced (since K+2N vs K is a draw). Here, White avoids the trade, in fact gives up a knight, and still draws!

The Problem

L. Kubbel & A. Herbstman, 1937

White to draw.

(Solution appears below.)

The Solution

Outro

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