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Hyper Fractal
The Hyper Fractal is an easy recursive setup for multiple T-Spin Doubles. Recursive in this case means, that after each T-Spin Double the board is in a similar state to setup the next T-Spin Double.
Introduction
for every piece there is a preferred spot where you want to place it. The S,Z and O-pieces should be placed on their stacks. the J-pieces are placed in the well atop each other. the L-piece is used to create the T-shaped holes. The I-pieces should be placed in pairs on the O,S or Z-Spots. And finally the T-piece is used for the T-Spin. When everything comes together it could look like this:
As an Opening
Let's look at an example
We initialize the Hyper Fractal main-stack with an I and an Z-piece.
That divides the board in 4 different partitions. On the left we have a 4-wide well that will be filled with J and L pieces to create the T-shaped holes and of course the T-pieces to clear the T-Spins. The main-stack is divided into 3 partitions: An O-Stack an S-Stack and a Z-Stack. Now the only thing to worry about is, where to place the I-piece. But luckily that can be solved if we place the I-piece in pairs we can place them on the O,S or Z-stack or we purge them horizontally in the 4-wide well.
But there is one further problem. At the start of the game we have placed to few pieces to start farming T-Spin Doubles and keep the Hyper Fractal going. So we need to build the main-stack first so that we have enough "fuel" for the machine. That means we need to figure where to place the L, J and T-piece on the stack. Luckily there are some ways to do that. L and J-pairs can build rectangles and can be placed on the O-Stack. Or we build a larger rectangle with the L,I and J piece. The T-piece is a bit tricky because it interacts with the S,Z-stacks. Placing a T-piece on the S-stack transforms it into an Z-Stack and vice versa. That means we need to place the T-pieces in pairs so that after the placement of both T-pieces we have again an intact S and Z-stack. There are of course other methods to build the stack. But for pedagogic reasons we are keeping it simple and formulaic at the moment.
-=pictures of J,L,I,T placements=-
Helpful advice
Another useful technique for balancing the stack is J-skimming (L-skimming in the mirrored setup) if the J-stack is to high. By rotating a J-piece instead of an L-piece, it creates a shape that can be cleared with either an S or a Z-piece. That operation just clears a J-piece from the stack so the board will be in the standard state again. It is also possible to place the S or Z-piece first and skim with J or L-piece later.
J,S,Z-Skimming:
Use J-piece |
to create S,Z-cave |
S,Z-cave |
Skim with S-piece |
Or skim with Z-piece |
Same result |