user3823: Here's a game of Atomic chess I played with a friend. As you may see, neither of us are very good at Atomic chess and the game ended in under twenty moves.
[FEN "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1"]
[Event "Casual game"]
[Site "http://lichess.org/I9pp1BLC"]
[Date "2015.06.17"]
[White "sethdj"]
[Black "Unihedron"]
[Result "0-1"]
[WhiteElo "1368"]
[BlackElo "1632"]
[PlyCount "32"]
[Variant "Atomic"]
[Annotator "lichess.org"]

1. Nf3 f6 2. Nd4 e6 3. e3 g6 4. Bc4 d5 5. Bb5+ c6 6. Qg4 Na6 7. c3 Nc5 8. Bxc6 {C6 capture removes itself and C5 knight.} Qb6 9. Qxe6 {E6 capture removes the queen herself.} Qa6! {Mate threat at Qf2# / Qg1#.} 10. Ne6! {Nuke threat at Nxf8#.} Bxe6 {E6 capture removes the bishop.} 11. d3 Qa4! {Mate threat at Qd1#.} 12. b3 Qg4! {Mate threat at Qd1#.} 13. f3 Qh4+ {Checkmate is now inevitable.} 14. g3 Qh3 15. Kd1 Qg2 16. Ke1 Qe2# { White is checkmated } 0-1

But that's not really the point here. The opening of 1. Nf3 f6 2. Nd4 is a very tricky knight attack, and when playing against a tricky player they may respond with Nb5 or Nf5 after e6 and c6 respectively, where e6 and c6 aims to protect those two grids. What is a good response here?

user7061: Black, who defends, should move its Knight to h6. There it protects f5 so if white moves its knight there, black can capture it. Additionally, if white does Kb5 with the intention to attack Black's Queen (and potentially king, if black attempts to defend the queen), Black can go forward (Ng4) and then Black wins: Black can either capture a pawn next to the king, or the queen if White moves this pawn, and white can capture the queen with some other pieces when black does Ng4, but black's king is still safe.
[FEN ""]
[White "White"]
[Black "Black"]
[Variant "Atomic"]

1. Nf3 f6 2. Nd4 Nh6 3. Nb5 Ng4 (3. Nf5 Nxf5) 4. f3 Nf2 5. Nxc7 Nxd1# 0-1

It can happen that white does h3 after Nh6 to block a potential Ng4 from black, and then black has to move a pawn to protect his pieces if white would move Nb5:
[FEN ""]
[White "White"]
[Black "Black"]
[Variant "Atomic"]

1. Nf3 f6 2. Nd4 Nh6 3. h3 c6


3823: <p><a href="http://lichess.org/I9pp1BLC">Here</a>'s a game of Atomic chess I played with <a href="http://chat.stackexchange.com/users/31465/seth">a friend</a>. As you may see, neither of us are very good at Atomic chess and the game ended in under twenty moves.</p>

<pre><code>[FEN "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1"]
[Event "Casual game"]
[Site "http://lichess.org/I9pp1BLC"]
[Date "2015.06.17"]
[White "sethdj"]
[Black "Unihedron"]
[Result "0-1"]
[WhiteElo "1368"]
[BlackElo "1632"]
[PlyCount "32"]
[Variant "Atomic"]
[Annotator "lichess.org"]

1. Nf3 f6 2. Nd4 e6 3. e3 g6 4. Bc4 d5 5. Bb5+ c6 6. Qg4 Na6 7. c3 Nc5 8. Bxc6 {C6 capture removes itself and C5 knight.} Qb6 9. Qxe6 {E6 capture removes the queen herself.} Qa6! {Mate threat at Qf2# / Qg1#.} 10. Ne6! {Nuke threat at Nxf8#.} Bxe6 {E6 capture removes the bishop.} 11. d3 Qa4! {Mate threat at Qd1#.} 12. b3 Qg4! {Mate threat at Qd1#.} 13. f3 Qh4+ {Checkmate is now inevitable.} 14. g3 Qh3 15. Kd1 Qg2 16. Ke1 Qe2# { White is checkmated } 0-1
</code></pre>

<p>But that's not really the point here. The opening of <code>1. Nf3 f6 2. Nd4</code> is a very tricky knight attack, and when playing against a tricky player they may respond with <code>Nb5</code> or <code>Nf5</code> after <code>e6</code> and <code>c6</code> respectively, where <code>e6</code> and <code>c6</code> aims to protect those two grids. What is a good response here?</p>
 7061: <p>Black, who defends, should move its Knight to h6. There it protects f5 so if white moves its knight there, black can capture it. Additionally, if white does Kb5 with the intention to attack Black's Queen (and potentially king, if black attempts to defend the queen), Black can go forward (Ng4) and then Black wins: Black can either capture a pawn next to the king, or the queen if White moves this pawn, and white can capture the queen with some other pieces when black does Ng4, but black's king is still safe.</p>

<pre><code>[FEN ""]
[White "White"]
[Black "Black"]
[Variant "Atomic"]

1. Nf3 f6 2. Nd4 Nh6 3. Nb5 Ng4 (3. Nf5 Nxf5) 4. f3 Nf2 5. Nxc7 Nxd1# 0-1
</code></pre>

<p>It can happen that white does h3 after Nh6 to block a potential Ng4 from black, and then black has to move a pawn to protect his pieces if white would move Nb5:</p>

<pre><code>[FEN ""]
[White "White"]
[Black "Black"]
[Variant "Atomic"]

1. Nf3 f6 2. Nd4 Nh6 3. h3 c6
</code></pre>
