Chess Opening Theory/1. d4/1...Nf6/2. c4/2...g6/3. Nc3/3...d5/4. cxd5/4...Nxd5/5. Na4

=Grünfeld Defence - Nadanian Variation=

5. Na4!?
This strange looking move was first employed by Ashot Nadanian in 1996. Usually it is not recommended to put Knights on the edge of the board, but here it is meaningful. White takes the important c5-square under control and going to force black's Knight from the center with е4. Eventually, the a4-Knight can occupy the c5-square and attack the pawn on b7.

Theory table
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'''1. d4 Nf6 2. c4 g6 3.Nc3 d5 4.cxd5 Nxd5'''