1. e5 Be5
2. Qd4 Bd4
3. Re6 Rf3
4. Nc6! Rf2
5. Nd4...

So white has iniciative and black has weak pawns on quenn side.

I think Black's weakness are the poorly protected pawns. Our knight is waiting to take c6 and d4 looks weak, too. Black will get serious problems on the queenside, if these pawns fall. A possibility to use this weakness is perhaps 1.e5, cutting off the bishop from protecting d4.

A natural answer could be:
1... Bxe5 and we have a plenty of possibilities:

a) Straightforward: 2. Nxc6 Qxc6 3.Rxe5
b) 2.Qxd4 Bxd4 3. Rxe6 and black can't protect the c pawn.
c) Perhaps we even have a rook sacrifice here: 2.Rxe4 Qxe4 3.Nxc6 with the idea 4.Qxd4+, winning two pawns. But perhaps it's a little bit overambitious.

So Black should find ways to protect it. 1...Rd8 allows 2.f4, consolidating the e-pawn. I don't think that's good for Black...

1...Rf4 looks better
2. Qb3 (of cource black can't allow the exchange) Qh3
Well... I think Black is better now.

Difficult puzzle today.