Logical patterns

 The following 3 diagrams share the same logical pattern. All 3 positions are larded with supportive one-movers. Let those not distract you. Logical patterns concern the whole combination. Albeit that the one-movers might steer the combination in a complete different direction. Let that not distract you.

USCF tactic 9

 

Diagram 1. Black to move

r1bR1Nk1/1p3pp1/2p2n1p/p7/Pq2PP2/2N4P/1PP3BK/1R6 b - - 0 1

Diagram 2. Black to move

3r1rk1/pp3ppp/4b3/3n4/1PR2B2/P6P/4BPP1/5RK1 b - - 0 1

Banusz, T. vs. Timofeev, Arty

Diagram 3. Black to move

2r2r2/p6k/1p2p2p/3b4/1P1b4/3NB1RP/PP4P1/2R3K1 b - - 0 1

Dijkhuis, Tycho vs. Ris, Robert

Notice how especially rooks in the middlegame are vulnerable for this type of combination. They have not enough space available to escape, and have a high value.

The salient cues are closely related to logic and not so much by geometrical patterns.