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Raetsky's Petroff Defense Everyman Chess gives the cochrane gambit as a good game for both sides. He likes white because of blacks poor center king position but gives the edge to black if he plays precisely.
And the only way for black to keep the edge is to play ... c5

i dont understand the c5 move white can capture 2 pawns and black has nothing...?
He has a Knight.
It's pretty dangerous stuff, and about the last thing a Petroff player wants to see.

What does a Petroffnik want to see? 1. e4 e5 2. Nf3 Nf6 3. Nxe5 d6 4. Nf3 zzzzzzzzz
All the people I have ever seen take up the Petroff did so to get an "easy draw" or a crafty win against White. This is why I have often played the Cochrane Gambit.
Black gets his Knight "advantage" and White gets a big blob of pawns and a shattered King-position for Black. Sounds like a game you can fight over.
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