Connect boards look easier than stacked ones and are lost in a completely different way. There is no height here: tiles sit in a flat grid, and a pair disappears when a path can be drawn between them through empty cells with no more than two turns. That single rule does all the work. It means the position of a tile matters less than the emptiness around it, that the outer ring is structurally cheaper than the centre, and that a grid can be half empty and still offer no legal move.
The path rule, precisely
Two matching tiles join when a line of at most three straight segments, meaning two corners, runs between them and every cell it crosses is empty. Most implementations let that line travel outside the grid, around the edge and back in, and that detail decides most of the tactics below. A pair sharing a row with a clear run between them needs no turn at all. A pair at opposite corners of an empty rectangle needs one, provided one of the two corner cells is free. Anything else needs two, and two turns means you need a clear lane to travel along.
Why an edge tile is already half solved
A tile in the middle of the grid can be approached from four sides and all four may be blocked. A tile on the outer row has the outside of the board as a permanent empty approach, so one of its two axes is open from the start and nothing can ever close it. A corner tile has two. That is the whole reason border work pays: every match made on the rim is cheap, and every tile pulled off the rim promotes the tile behind it into the same privileged position.
The consequence runs opposite to stacked layouts, where the interior of a flat slab is exactly as hard as its outside. On a connect grid, working inwards from the border is correct, and players arriving from tall stacked boards often start in the middle out of habit.
Keep one corridor open
A single empty row or column running the width of the board is worth more than a dozen scattered gaps. Anything able to reach that lane can reach anything else on it within two turns, which converts a large part of the grid into one connected pool. Once a lane is open, resist the urge to wander: clear the tiles that would let a second lane form across it, and the two together cover most of the board.
The reverse is the commonest slow death in this format. Clearing pairs evenly all over the grid leaves a lace of isolated empty cells, none of them joined to anything, and a board that is a third empty with no route between any two matching tiles.
Count turns before you click
Learning to see the path is worth more than any list of tips. Trace it with the eye in a fixed order: straight line first, then the two single-corner routes, then a lane with two corners. If none of the three works, the pair is not available yet and the click will do nothing. Doing this deliberately for a few boards makes it automatic, and it puts an end to the aimless clicking that eats the clock on timed grids.
What happens when the grid moves
Many boards in this family apply gravity after each clear: tiles fall downwards, slide left or right, or the whole grid pulls towards the centre. The map therefore changes every time you play, so long plans are worthless and one clear ahead is the right planning horizon. It also hands you a tool. Where tiles fall downwards, clearing a pair low in a column drops everything above it, which can drop a matching tile into the empty row you have been protecting. Choose between two equal pairs by what the collapse will do afterwards.
On a board with no gravity the opposite holds. Holes you make are permanent, so it is worth placing them deliberately along one line rather than wherever the easiest match happens to be.
The centre block
Sooner or later the rim is gone and a solid rectangle remains in the middle, and this is where boards are lost. A tile inside a full block has no empty neighbour, so nothing in the interior is reachable and the block can only be eaten from its own outer ring. Attack it at a corner rather than the middle of a side: a corner tile opens two approaches at once, a side tile opens one. If the block is large, work one face of it steadily instead of nibbling all four, so that the empty space you create stays joined up.
Stalled grids and what a shuffle moves here
A flat grid stalls in its own particular way. There are usually plenty of empty cells left when it happens; what is missing is a route between any two matching faces, because the empties are scattered instead of joined. A shuffle does something different here from what it does on a stacked layout. It redeals faces into the same occupied cells, and since the difficulty on a grid comes from which cells are empty rather than from what covers what, that redeal genuinely changes which pairs are reachable. Shuffling is worth more on a flat board than on a stack, which is not a reason to spend one before checking whether a single corridor would have solved the problem for nothing. Mahjong Link is one of the layouts kept on this site.
Where to practise
The connect boards cover the flat-grid family, including the link and onet variants that run on the same two-turn rule. Butterfly Kyodai is a good place to learn path-tracing because its grid is dense enough to punish careless clicks, and Onet Mahjong is the plainest statement of the rule. If the board in front of you stacks tiles as well as linking them, the removal-order argument in the solitaire order of play applies instead, and the strategy pillar covers where the two families part company. A layout of that kind in the catalogue here is Mahjong Connect 2.
