Other Fish

Beyond 2-Fish

If you are new to Candie Markup (pencil marks), then I would suggest that you first make sure you can handle 2-Fish, Sashimis, and Splatterfoots with ease. At that point, you can come back and read about the higher-order Fish described on this page.

From reading the 2-Fish page, you know that a 2-Fish is a Twin-based concept.

3-Fish may involve Triplets. 4-Fish may involve Quadruplets. A House has Triplet 9s when it contains exactly three 9-candies. Or it has Quadruplet 9s when it contains precisely four 9-candies. (Same for 8s, 7s, 6s, . . .)

The generic term for Twins, Triplets, Quadruplets, . . .  is Lookalikes.

People have gradually discovered a significant number of Lookalike-based Tactics that go beyond 2-Fish. Almost all these Tactics bear the name of some sort of fish.

These higher-level Fish Tactics have two disadvantages in comparison to ordinary 2-Fish:

• they tend to be harder to spot;
• they often do not produce a Kill.

So, in fact, I'm not very careful about applying these Tactics — which must make you wonder why I mention them at all. Well, for one thing, maybe you're more careful than I am. And these ideas are part of the culture, so you might want to know about them just for that reason. Furthermore, they all deal with reasoning about Lookalikes, which is good for your mind.

Below, I will make some very brief remarks about standard 3-Fish and 4-Fish, and then for the others I'll refer you to external web sites.

 

3-Fish

External synonym:  swordfish.

This is the first-discovered Lookalike-based Tactic that bore the name "fish" (a 3-Fish is called a swordfish). The name caught on, and subsequently nearly all Tactics based on arrangements of Lookalike candies (Twins, Triplets, Quadruplets, . . .) were referred to as Fish. Apparently, to the discerning eye, a swordfish can be perceived in the 3-Fish Lookalike pattern in the same way that some people can see a great bear in the Ursa Major constellation.

A swordfish is usually taken to mean a Row-Based, Column-Framed 3-Fish (or its 90-degree-rotated variant). Here's an example:

Row-Based 3-Fish. Each of the three green Rows holds either Twin 2s or Triplet 2s. For the purposes of this example, a green Cell marked with only a dash ("—") must not hold a 2-candie (it could hold other candies, or it could hold a non-2 BigNum). These Lookalike 2s happen to fall in three "Frame" Columns. All 2-candies in the yellow Target Cells are killed.

3-Fish are more complex than 2-Fish, since each of the 3 Rows here can hold either Twin 2s or Triplet 2s.

The reasoning that justifies this Tactic is similar to the argument given in 2-Fish. Just try placing a BigNum 2 in some Cell in one of the Target Area Columns:  this leaves only two yellow Columns available to hold the three BigNum 2s for the three Rows. But two Columns can't hold three 2s, so the attempt to place a 2 in the Target Area fails.

As usual, if you rotate this example by 90 degrees, you will get a Column-Based, Row-Framed 3-Fish.

But we have to talk about the fact that 3-Fish are hard to spot. Are they worth looking for or not?

As I look for 2-Fish, I occasionally notice a 3-Fish, but it's rare to find a 3-Fish that actually produces a Kill. So the truth is, I don't look for them very carefully.

Do I pay a price for that?  Yes and no.  Sometimes some other Tactic kills off the candies that a 3-Fish would have gotten. At other times (but fairly rarely), I've applied everything but Chains, and I still have an unusually high density of candies-per-empty-Cell on the Grid, so I figure I may have missed something. At that point I check for missed Claims (which I'm a little prone to overlook if a new Claim has been created by some Kill); and then, somewhat begrudgingly, I might look for 3-Fish. I'm seldom rewarded, of course; but if I actually do find a 3-Fish that has a Kill, that often cracks the Sudoku.

So you have to figure out by your own experience what your policy on looking for 3-Fish is going to be.

 

4-Fish

External synonym:  jellyfish.

A jellyfish is usually taken to mean a Row-Based, Column-Framed 4-Fish (or its rotate-by-90-degrees variant).

Here's an example:

Row-Based 4-Fish. Each of the green Rows holds Twin 7s, Triplet 7s, or Quadruplet 7s. A green Cell marked with only a dash ("—") must not hold a 7-candie. These Lookalike 7s happen to fall in four "Frame" Columns. All the 7-candies in the yellow Target Cells are killed.

Occasionally, I notice a 4-Fish. I have never seen one that would produce a Kill.

 

And Yet More Fish . . .

There's really no end to the varieties of Fish.

There are two other major groups of genuine Fish I've seen discussed:

• frankenfish;
• mutant fish.

For a Fish of order 3 or higher, if you still insist that the Base Houses be of the same type (all Rows, for example) but you allow the Frame Houses to be of different types, you have a frankenfish.

And if you relax the above restriction by allowing the Base Houses to also be of different types, then you have a mutant fish.

But for both frankenfish and mutant fish, it's hard to recognize the pattern in a real-world Grid, and that leaves me dubious about their importance.

See Links for references to frankenfish and mutant fish.

 

And Fishy Things . . .

These are the two groups in question:

• kraken fish;
• fishy cycles.

For both of these, they're not really Fish, as the notion of well-defined Bases and Frames has disappeared.

I've seen kraken fish described as "a Fish on life support". This is not some kind of insult. It's just that a kraken fish is an almost-fish whose very nature depends on what's going on in some external Cell.

As for fishy cycles, some of the discussions are clogged up with terminology that I think tends to lead the reader astray from the gut issues involved. My general feeling is that I can accomplish with Chains, as I view them, the same sorts of things that people use fishy cycles for.

See Links for references to kraken fish and fishy cycles.