Mattock puzzle solution
Red creates a whirligig in the northeast, and removes Blue’s miner in the southwest. Red also could have created an arc, t-rex, or diamond at A, B, or C to prevent Blue’s invasion in the northeast—though a diamond would have blocked protected spaces that Red needs in the endgame. Because Blue must replace his removed miner, connecting to Red’s isolated miner on the next turn will cause Blue to have two adjacent miners. Blue must move both of these miners to provide a clear path from Red’s isolated miner to two of his own miners, and needs two turns to do so. This gives Red another turn to mine in the west, bringing her isolated miner one space away from connection to the main group. Note also that if Blue connects to Red’s isolated miner, it will create a t-rex that blocks his own ability to connect through the centre of the board, giving one open space to Red.