As discussed in the previous post, the natural tendency is to try to build material up into the top row via the far corner. But don’t be deceived! As tempting as it feels, it’s rarely correct. We present here a fairly advanced technique, in the spirit of alternating between basic strategic building blocks and more advanced ones. (Don’t worry, sometimes we’ll just do pretty pictures too.)
The best way to aggregate material in your top row is via the shift-combine. This is a move wherein you combine multiple blocks up from the second row into the top row with one move. In order to do it, you need to first line up blocks in your second row that match the ones above them in the top row. This is usually accomplished by moving Right and then Up - hence, the shift (Right) and combine (Up).
In this gif, you can see the shift-combine happen at the end. The player is building up her second row like a mirror of the top row, but with the biggest block being equivalent to the second-biggest top row block.* When she has everything in place, she completes the mirroring by moving Right, combining her Treycees (12s) into a Tristine (24) and then combining the resulting second row Up with the top row.
Though the shift-combine is a difficult move to master, the payoff is huge. The alternative (combining material leftwards across your top row) leaves a gaping hole at the right side, which will be quickly occupied by incoming filler blocks (1/2/3). Having such small blocks in your top row can be a big problem, since it can become hard to move large material out of the middle of the board.
Over the next day or two, we’ll post some pretty stills of successful shift-combines to illustrate the point, in (many) fewer words.
*This is a common pattern, where your top row is occupied and you wind up playing what is effectively a sub-game in your bottom three rows at a lower level.