Puzzle of the week #306

Level: 
5-Queen
Chess Diagram: 

[Event "Puzzle #306"][Date "2017.01.13"][Result "0-1"]1. d4 d5 2. c4 e6 3. Nc3 c5 4. Nf3 Nc6 5. e3 Nf6 6. Be2 Be7 7. O-O O-O 8. a3 a6 9. dc5 Bc5 10. b4 Ba7 11. Bb2 Re8 12. Qc2 Qc7 13. Rfd1 dc4 14. Ne4 Ne4 15. Qe4 b5 16. Be5 Ne5 17. Ne5 Bb7 18. Qf4 Bb8 19. Bf3

At move 14 white decided to sacrifice the c4-pawn for no particular reason. Black took it, made sure it could hold onto it by creating a solid pawn chain on the Queen side and then lined up his Bishops and Queen toward White's castle position. Right now white has just offered an exchange of the light squares Bishops, betting on the fact Ra8 could be under attack (Bb8 cuts-off the connection between both Rooks) and defending it could give him enough time to play a crushing Rd1-d7. Your tasks as black and having to move:
a) What is the name of the opening
b) Analyse the position and put together a plan or combination to counter white's idea
c) Play the best line you can come up with
Total available points for this puzzle is 25. The answers will be published next time together with puzzle #307.

Puzzle #305 solution:
The best answers were provided by Coco and Cody.
a) Material: equal
Development: black has developed 2 knights and a queen, while white has developed 2 knights and a bishop. Black's c8-bishop is blocked and the c3 knight is pinned (absolute) to the king.
King Safety: Both sides have not castled yet, but I believe white's king is in more danger because the queenside pawns have advanced while the king is still in the center, the c3 knight pinned.
Pawn formations: white has one pawn chain, while black has 2 supporting the d5 pawn.
Center: There are 2 pawns in the center, supported by other pawns and pieces. Both white knights, the d3 and c4 pawns, and the queen control it, while black has a knight, c6 and e6 pawns, and a queen controlling it.

[Event "Puzzle #305"][Date "2016.12.12"][Result "0-1"][SetUp "1"][FEN "r1b1kb1r/pp3ppp/2p1pn2/q2p4/2PP4/P1N1PN2/1P3PPP/R2QKB1R b KQkq - 0 8"]8... Ne4 9.b4 (9.Rc1 Nxc3 10.Rxc3 Bxa3! {Black has won material and has a very solid position}) Bxb4 10.axb4 Qxb4 11.Rc1 Nxc3 12.Qd2 Na2 {Black is up 2 pawns}

Correct solutions:
Coco, Cody - 20 points
Bradley, Deryk - 10 points
Uros, Benjamin, Dheera - 7 points
Jalen - 6 points

Standings:
Coco - 95 points
Cody - 94 points
Jalen - 73 points

Deryk - 72 points
Bradley - 70 points
Benjamin - 61 points
Uros - 45 points
Yakov - 36 points
Dheera - 25 points

Comment: 

QGD