Another fairly basic Tak shape is a ladder — two pieces with touching corners. A ladder isn’t fully connected yet, but there are two ways to do so. Thus, it is pseudo-connected because you are guaranteed an opportunity to fully connect. Ladders do not immediately extend in either direction, but open up an extra lane for expansion in both. Although a ladder may have a specific direction in mind, this is strictly a consequence of its surroundings — on its own, it is perfectly noncommittal. In this way, ladders are very difficult to defensively pin down; if your opponent defends one direction you can simply reroute along the other. The ladder effectively indicates that you are waiting to see what your opponent is up to and plan to react accordingly.

Since ladders are a “wait-and-see” shape, it’s worth talking about their follow ups. Obviously, if your opponent intrudes on one of the crucial points it is no longer a pseudo-connected shape, so you will want to play locally unless there is very high-value move elsewhere. Note that the presence of such a high-value move should be uncommon, as it would also shift your opponent’s priorities away from the ladder. Thus, ladder intrusion indicates that this area is now a point of contention and invites a local response. Unless you have other resources that you want to relate, finishing the connection (aka taking the other crucial point) is your best bet.

You could also elect to create an extended ladder by adding more corner-touching pieces along the same diagonal. This continues your wait-and-see policy, but has diminishing returns in terms of expansion because it commits extra full-connection moves in the future; in other words, increasing your longest path along the diagonal is slower than along the vertical/horizontal because it takes more pieces. But despite the expansionary slowness, it firmly takes lanes of expansion away from your opponent — they will not be able to build through your ladder without it being a Pyrrhic victory.

In contrast to a basic ladder, an extended ladder is not quite pseudo-connected; your opponent could cut the shape with multiple walls/caps and at least one capture. However, this would be a significant defensive investment. In this way, extended ladders are the first of a broad class of powerful shapes which I will refer to as strongly connected — requiring multiple walls/caps AND at least one capture to cut. Additionally, a cut ladder can shift it’s focus to a single direction without losing local tempo.

A more direct follow-up to a ladder is simply adding partners. As per my discussion on partners, you primarily want to do this when you’re sure that this is an area of contention or have time to press the initiative. Unless the partner fully connects the ladder (more on that later), it constitutes a directional commitment that gives your opponent a heads up about where they can try to block you. Note that this is the transpositional equivalent of following up partners with a ladder, and though it has a directional focus it is not fully committed to a single lane in that direction.

As with partners, the edge of the board has a big impact on how ladders operate. One of the most powerful uses of a ladder is in developing out of a corner. By pseudo-connecting to the corner you immediately make it relevant to all your future plans. This isn’t as flexible as central partners because half of it’s development lanes are edge-bound, but by incorporating the corner you are being efficient with your pieces without committing to an edge-crawl. Additionally, the directionally ambivalent nature of ladders is well suited to the corner, where you have a preexisting edge connection in both directions simultaneously. Note that for quite the opposite reasons, a ladder that develops ‘around’ a corner (i.e. the only way to make a ladder where both pieces is on an edge) is quite weak — this is basically an edge-crawl that doesn’t gain any tempo (arguably the only thing that edge-crawl is good for in the first place).

Ladders off the edge are not quite as intuitively powerful as ladders out of the corner. Although it is pseudo-connected to the edge, the directional flexibility isn’t particularly potent since some of your lanes of expansion would be edge-crawls. Moreover, partners arguably do a better job of extending off the edge because you don’t have to futz around with the minor tempo-distinction between fully and strongly connected. It is also a little bit easier to build through a ladder than it is to build through partners, and so it offers less of a defensive deterrent.

A ladder with a capstone is extremely potent. In fact, a preexisting capstone arguably benefits far more from a ladder than a partner. One of a cap’s most important functions is to control an area of contention (an area through which both you and your opponent are trying to build). At least at first, your cap doesn’t really need a partner to fulfill this role; and more importantly, the ladder’s lack of directional commitment gives the cap more potential to play an active role. Moreover, caps move so strongly that you don’t necessarily need to respond to an intrusion by taking the other crucial point. The cap opens up a plethora of options that morph seamlessly into a local victory, even when doing so involves taking prisoners.