# Template VI1/Other Intrusion on the 1st row

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This article deals with a special case in the defense of edge template VI1a, namely the right-hand ('other') intrusion on the 1st that is not eliminated by sub-templates threats.

## Basic situation

Red should go here:

The Red 1 hex is connected to the bottom, and threatens to connect to the top through either one of the "+" hexes. It is now Blue's move.

## Claim #1: Blue must move in one of the following + squares below

If Blue moves to

If not, Red can move to either i3 or i4 and secure a connection.

## Proposed first Red response

If Blue moves to {e7, f6, f7, g5, g6}, Red should take i6 and force a Blue response in either i3 or i4. If Blue moves to {h6, h7, i5, i6, i7}, Red should take f6 and force a Blue response in either i3 or i4. If Blue takes i3 or i4 direcly, proceed with Response to i3 or Response to i4 instructions below.

## Response to i3

If we've arrived here, Blue has just taken i3, i4 is free, h5 is securely connected to the bottom and Blue has at most one of the "+" squares below (with one exception; see i3 addendum). In this case, Red should first take j3 and force a Blue response at i4:

CASE #1: Blue has i5. SOLUTION:

CASE #2: Blue has no tiles in {h6, h7, i5, i6, i7}, or has either {h6, h7, i6} (indicated by +). SOLUTION:

CASE #3: Blue has i7. SOLUTION:

Blue must take one of the + hexes or Red wins. Now, Red can play i6 and force h7, then play h6 and connect to h5 (which is already securely connected.

## Response to i4

If we've arrived here, Blue has just taken i4, i3 is free, h5 is securely connected to the bottom and Blue has at most one of the "+" squares below (with one exception; see i4 addendum). In this case, Red should first take h3 and force a Blue response at h4:

CASE #1: Blue has g5. SOLUTION:

CASE #2: Blue has no tiles in {e7, f6, f7, g5, g6}, or has either {f6, f7, g6} (indicated by +). SOLUTION:

CASE #3: Blue has e7. SOLUTION:

Blue must take one of the + hexes or Red wins. Now, Red can play f6 and force f7, then play g6 and connect to h5 (which is already securely connected.