Work in progress
MDF, also known as (Mini Double Fractal) is an opener created by benmuga which makes a T-Spin Mini or a 1 line skim followed up by a TSD and either a Perfect Clear with I J or L ending or a Fractal.
The idea of it is to create TSD's, and if possible, spike with the Fractal and continue making TSD follow ups.
It has a variety of second bag combinations, so MDF can be used depending on the piece sequence or how the user wants to make the second bag; cheese, spikes or better TSD follow ups.
MDF can be used in various first bags, as long as they fit these dependencies:
1.- If L is used first, J must be used after Z.
2.- if Z is used first, S must be used after L.
Those rules applies not exactly right after your Z or L are placed, but they must follow that order independent of the other pieces on the same bag, and both rules are expected to be on different bags.
Some tips to memorize the opener easily and have a higher success on MDF build are:
1.- DAS O all the way to one of the walls
2.- If O is placed on the right wall, Z comes next to O
3.- With the example of tip 2, on the left wall L and S comes together
4.- Always start building what is next O piece. (Z and J, or S and L if mirrored).
First bag
Basic formation
The first bag can be built like this (although you can do the T-Spin Mini Single first and put the I later if needed.)
Variations
- Octuple8's variant: This variant can assure you the TSM if J and L are early due to leaving no piece dependencies for the formation on both sides after placing both pieces.
- Agent RO's variant: This variant has has the least piece dependencies. You only need an S piece before I and Z.
Second Bag
4-line Perfect Clear
If your second bag begins with OTJ or OTI, you have a 16.19% chance to get a Perfect Clear (2 solutions).
Fractal
If getting a Perfect Clear is not possible, you can easily make a Fractal using the three main setups or the two alternative setups, as long as you get the J piece before S.
Form 1: L → O (L comes before O in the second bag)
Form 2: O → LI (O comes before L and I in the second bag)
Form 3: O → L (O comes before L in the second bag; compromise)
You only need the three setups above, but the alternatives below are also possible.
Form 4: O → Z (O comes before Z)
Form 5: Z → O (Z comes before O)
TST
TSD-TST/Incomplete TST setup
If you get an S piece before J, which therefore means you cannot make a Fractal, you can always make a T-Spin Double, which in turn, will make the T-Spin Triple. At that point, you simply need to make the overhang and fill in the rest.
Third Bag and Onwards
T-Spin Triple
If you get your third bag T early (with only your L and I before it), you can build a T-Spin Triple.
This works regardless of whether you used early or late O for the second bag, but early O is preferred as late O requires you to use a few extra pieces.
Triple Fractal
This continuation only work if O comes later than L in the second bag. You also need an early O in the third bag.
King crimson
4-Wide
6-3
TSS instead of finishing with TSD
