To the best of my knowledge, there is always a way to open with a T-Spin Double (TSD). More interestingly, there is always a way to open with a safe
TSD. The reason I say that is because I have found that I can always do a single bag
TSD from the start of the game. The purpose of this article is to show how.
Modern Tetris games use the bag randomizer
. There are 7 pieces: I, T, O, S, Z, L, and J. The the first 7 pieces the game gives you will consist of one of each (in random order). This is the first bag
of pieces. The next bag will consist of the same 7 pieces, but in another randomized order.
Single bag TSD openings appeal to me for the following reasons:
- They send the same number of lines as a Tetris, but require less pieces.
- There's minimal upstack commitment. They don't require risky overstacking, which means I can quickly access my garbage after doing them. A bag is made up of 7 pieces. A TSD clears the equivalent of 5 pieces off the field. That means there's only 2 pieces worth of "stuff" left scattered over the surface once finished.
- They lend well to a follow-up TSD or T-Spin Triple (TST).
- In most cases, they won't require soft dropping to get the field back to normal afterwards.
- Using the first bag's T towards the actual T-Spinning is extremely efficient when planning to do multiple T-Spins in succession. Doing so frees up the next bag to do another TSD. Compare this with for example a DT Cannon or C-Spin opening. With those, you must use the first T piece towards the stack (and not the TSD line clear). As a result, you must use the next bag's T to complete the first TSD (or TST). The third bag's T goes to the second TSD or TST. That could mean you might need to wait upwards of 21 pieces in order to get the T you need to complete the second TSD or TST. Instead, if you open with a single bag TSD, then you'll use the freed up second bag's T towards the second TSD or TST and need only wait a maximum of 14 pieces for it.
A single bag TSD requires you to place the T last (which clears the lines). (There are actually a couple rare exceptions where the TSD can be done with one piece left over from the first bag, but let's ignore those for now.) A couple of rules result from this:
- The T won't always come dead last. So, almost 6/7ths of the time, you will need to hold it until you've first placed the other pieces.
- Once you hold the T, you won't be able use the hold button again until the end of the bag.
There are 5,040 possible bags. In order to always
open with a single bag TSD, you must know a number of different openings. You must also makes sure to notice the opening pieces before
choosing which to do. Without proper planning, you might start the wrong opening and not have the right order of pieces to finish it. TKI T-Spin Double
The most famous and popular single bag TSD is the TKI opening. It was first outlined by the Japanese Tetris DS player TKI
. Since then, it has caught on like wildfire. I always try to do this first (when the bag allows for it) due to how well it allows for multiple follow-up TSDs. The core principles behind the TKI are:
- Recieve the I piece early
- Place the I piece flat and dead center
- Place the L/J with regards to its complementary Z/S (I'll elaborate on this a little later)
We cannot do the TKI when following types of bags occur:
Make sure to check for these cases before committing to the TKI!
- S, Z, and T all come before the I piece.
- J, L, S, Z all come before O and I
- Z and T come before I, and L comes before O and S.
- S and T come before I, and J comes before O and Z.
With practice, it only takes a glance before knowing the opening bag won't work. Moreover, be sure to do the TKI when it is possible! If the opening bag allows for it, but you're unsure at first glance and decide to do something else instead, chances are that the TKI might've been the only possible single bag opening in the first place. It's better to be sure than to rush into something and fail.
There are a few variations of the TKI to become familiar with:
- Castle top variation
- Snail variation
- Fonzie variation
- Flat top variation
Always look ahead to see whether the S or Z comes first. Whichever comes first will determine how to place the L or J. This becomes especially important when having the T in the hold chamber (and thus preventing the use of the hold function until the end of the opening bag).
For example, let's say the opening bag is TJZILOS. Of course, first we'll hold the T. Next, we can place the J in one of two ways:
In the first case, the player neglects to look ahead and drops the J against the surface in its letter orientation. This results in a busted opening. The first squiggly
piece to come is the Z. The Z is complementary to the L (as the S is complementary to the J) when building a T-Slot. For that reason, you'll instead want to use the L
in its letter orientation. So, you should place the J horizontally on the other side for now. This is what happens in the second case (shown above).
The take away message from this:
- Look ahead!
- If the Z comes before S, plan to place it horizontally on top of the I piece.
- Plan to place the L in its letter orientation in order to complement the Z.
- Vice versa if S comes before Z.
Having the T in the hold chamber will sometimes force you to drop either one of the S or Z pieces before getting to the I piece. (But not both S and Z, since a TKI is not possible when S, Z, and T all come before the I.) Save this manuever as a last resort, since it requires an extra soft drop (which slows you down).
variation is really only needed when:
- Z and T come before I, and L comes after either O or S.
- S and T come before I, and J comes after either O or Z.
- The castle top variation results from L/J coming after O, and the flat top variation results from L/J coming after S.
Castle top continuation examplesSnail continuation examplesFonzie continuation examplesFlat top continuation examplesSources and further reading for the TKIPlatformed single bag T-Spin Doubles
- Z and T come before I; O comes before L
- S and T come before I; Z comes before J
When the opening bag doesn't allow for the TKI (e.g. if S, Z, and T all come before the I), then you can still do a single bag TSD by using one of several platform methods. The unifying idea behind these openings is that the TSD is platformed
over the bottom-most row and is cleared on rows 2 and 3.
The following 13 variations are able to handle any bag that the TKI cannot. Some of them may in fact be unnecessary, but they're good to know just in case you mess up one of the more obvious choices.Albatross Opening
- Cradle variation
- Cornerstone variation
- Single gap variation
- Double gap variation (use as a last resort)
- Cradle variation
- Cornerstone variation
- Long platform variation (use as a last resort)
- Jagged prop variation (use as a last resort)
Dodo Opening (used only for rare, super evil bags)
- Skateboard variation
- Corner gap variation
- Center gap variation
- Cradle variation (use as a last resort)
There are three types of bags to become familiar with when deciding which platform TSD to open with:
- Early O: open with any variation other than the Pelican skateboard, Pelican cradle, or Dodo.
- Late O: open with either the skateboard or cradle variation of the Pelican.
- Early T that forces a either S/Z to be played first, but unable to do any Pelican variation (e.g. TSZOILJ): open with the Dodo.
When the O comes late, and you need to place both S and Z first, this forces the skateboard or cradle variation of the Pelican. In all the other platform openings, you prop one of the S or Zs on the O. For this reason, make sure to look ahead in the bag to see where the S and Z are in relation to the O. Since the Pelican carries the burden of all the late O situations, and since the skateboard variation doesn't require an extra soft drop like the cradle does, the second most used opening after the TKI should likely be the skateboard variation.
The next two most used openings (which you use for early O situations) likely should be the Flamingo cradle and the Albatross cradle. The reason for this is that the cradle variations tend to be safer. When using, for example, a cornerstone variation of either the Flamingo or Albatross, the success of the opening becomes more sensitive to the particular order of pieces that come. With a cradle variation, there's less to look ahead for to make sure it's possible.Choosing between the Flamingo or the Albatross
When you get an early O situation, look ahead before placing the first piece. Check to see if L comes before J or vice versa. This will tell you which opening will lead to the cradle variation.
For example, let's say we get ZOJTLSI. We can turn this into either a Flamingo or Albatross:
In this case, since the J came before the L, a cradle can't be done with the Flamingo, but can be done with the Albatross.
If instead we get OZLJTIS we can do one of either:
Here, the Flamingo leads to a cradle variation, but trying to do the Albatross leads to a busted opening.Albatross continuation examplesPetrel continuation examplesFlamingo continuation examplesPelican continuation examplesDodo continuation examplesSources and further reading for platform TSD openingsFinal notes
It took me a couple weeks of practice before I really began to understand what to look for in the opening bag. Now I can pretty much do a single bag TSD every time. Games like Tetris Friends where you don't see the next pieces until the game has already started are much more difficult to do quickly off the bat. However, with enough practice, it should only take a glance to know which opening will work.
Sometimes it just doesn't matter what you do in the beginning. With clean garbage due to the change on attack mechanic, often it just goes back and forth anyway. Despite that, using these methods correctly can result in a consistent and stable opening. Once they've been mastered, it becomes much easier to focus and improve on other tactics. You won't have to worry about figuring out how to deal with an awkward opening bag anymore for example.