fredthebear: This Fraser Defense matches the initial central exchange of the Stafford Gambit in the Petroff defense, but feels much slower for Black. What are the odds your opponent has prepped for the Fraser Defense? If White finds 4.Qh5+ as referenced by <ajile> above, it does not seem that much White prep is required to get the jump on Black after 4...g6 5.Nxg6 Nf6 6.Qh3 etc. An experienced player should have no trouble finding/recalling this approach, but there are plenty of players lacking experience with the Latvian counter-gambit.
Latvian counter-gambit
C40 Sub-variants:
King's knight opening
1. e4 e5 2. Nf3
Gunderam defence
1. e4 e5 2. Nf3 Qe7
Greco defence
1. e4 e5 2. Nf3 Qf6
Damiano's defence
1. e4 e5 2. Nf3 f6
QP counter-gambit (elephant gambit)
1. e4 e5 2. Nf3 d5
QP counter-gambit, Maroczy gambit
1. e4 e5 2. Nf3 d5 3. exd5 Bd6
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Latvian counter-gambit
1. e4 e5 2. Nf3 f5
Latvian, Nimzovich variation
1. e4 e5 2. Nf3 f5 3. Nxe5 Qf6 4. d4 d6 5. Nc4 fxe4 6. Ne3
Latvian, Fraser defence
1. e4 e5 2. Nf3 f5 3. Nxe5 Nc6
Latvian gambit, 3.Bc4
1. e4 e5 2. Nf3 f5 3. Bc4
Latvian, Behting variation
1. e4 e5 2. Nf3 f5 3. Bc4 fxe4 4. Nxe5 Qg5 5. Nf7 Qxg2 6. Rf1 d5 7. Nxh8 Nf6
Latvian, Polerio variation
1. e4 e5 2. Nf3 f5 3. Bc4 fxe4 4. Nxe5 d5
Latvian, corkscrew counter-gambit
1. e4 e5 2. Nf3 f5 3. Bc4 fxe4 4. Nxe5 Nf6