List of Tactical Motifs v0.1

Here is my list of tactical motifs; any and every combination should be able to fit into one of the categories (I'm not asking for much am I?). I've used Informant's "Encyclopaedia of Chess Middlegames" as the basis of the list; each one will need a clear definition and illustrative example.

1. Double Attack
2. Forking
   
3. Discovered Attack
4. Pinning
5. Deflection
6. Decoying
7. Interference / Interception
   
8. Annihilation / Removal of Defender
9. Clearance
10. Blockade
11. X-Ray Attack
12. Overloading
13. Zwischenzug / Intermediate Move
14. Pawn Breakthrough
15. Passed Pawn
16. Demolition of Pawn Structure
17. Pursuit
18. Zugzwang
    

Of course there are problems with this list before I even begin... the redoubtable Mr. Averbakh again points out that all tactics are a form of (1) Double Attack. Indeed there are even 'positional tactics' where by threatening to gain one type of positional advantage (say a doubling of the opponent's pawns) the defense allows you to gain a different positional advantage (say control of an open file). Perhaps we will rename this one 'Barrage' - attacking a piece with more pieces than defend it, as this most simple idea isn't explicitly covered in the other categories.

Zugzwang and clearance have an interesting inter-relation, we might call them both 'tempo tactics' at opposite ends of the scale; with Zugzwang you compel the opponent to gain a move to his own disadvantage, with clearance the piece that moves to clear a square or line usually does so compelling the opponent to defend a threat that effectively loses a move with respect to defending a secondary threat. Clearance and discoveries are also closely related, clearance usually referring to position (squares and lines) whereas discoveries usually refer to material.

The list needs a little work, it could perhaps be more concise, but it's a start... now to the definitions!