Beacon

Named so as the pattern of ISZ resembles an unlit Beacon. This opening template existed beforehand in the Japanese Community as スピアード積み(Speerde Stacking).

After Kaidan this opener aims for stable 6-3.

General Shape

To rotate the I into position J, LO, or JOL tetrominos must be placed if not performing a wallkick. In games with symmetrical I rotations this cannot be done with J alone.

The First Bag has a 20.00% Perfect Clear chance, 3 solutions.

Main Stacking Method

This can be assembled 85.56% of all bags with one soft-drop, or 90.87% for two or more.

With mirror these values become 92.38% and 95.24% respectively.

Heart Variation

By alternating the heart shapes this covers 78.89% of all bags, resulting in favourable residue to freestyle 6-3.

Common ideas are to keep L or O in hold to fix height difference after a floating T-spin.

Other frequent stacks include the folllowing, the latter of which results in a 51.75% Perfect Clear chance with other Perfect Clear continuations that lead to a potential loop.

These Mechanical TSD setups are also possible with potential for Perfect Clears (see link):

• TSS Hamburger: This is best used when possible to hold I but is otherwise highly freestyle afterwards. Ideal stack and continuations shown.

It is possible to TST with a 90.44% Perfect Clear chance, 5 solutions or continue 6-3, note SZ pieces cannot always be placed as shown but the JO order can be swapped.

S>L

L>S

Mismatched Heart

It is also possible to stack like so 50.00% of the time when the LS heart shape comes in the wrong order. A mismatched OJ is possible, but entirely freestyle.

• L>S:

• Else Freestyle:

All Cover Variation

Covers 100% of bags, can be used independently or when the Heart variation fails.

• L>O:

• TSD: Look for which of L or S come first. If possible place S/Z as in diagram two after taking a T-spin, otherwise place Z rightmost always.

• STSD This path covers 100% of bags (note I spin will not work mirrored in SRS games) Created by ponix1.

For the first diagram, the I piece can be placed by soft dropping onto the edge of the Z piece, going left (right for mirrored), soft dropping, then rotating CCW (CW for mirrored). If the L piece has not been placed yet but the Z piece has, then a precise set of inputs can be made to prevent any waiting: soft drop onto the edge of the Z piece, go left, soft drop, go right into the small hole, rotate CCW (CW for mirrored), then go left.

For the second diagram, if the J and O pieces have already been place, the S piece can be placed by rotating CCW (CW for mirrored), soft dropping onto the ledge of the J piece, rotating CCW, soft dropping, rotating CCW, then going left.

With practice, these inputs can become second nature.

The I piece may need to be placed in the well or vertically to the side. The first diagram is ideal and commonly buildable.

• O>L: For the sequence SJO use the last diagram, provided by metallicLurker, when unable to hold. The second template will suffice for 180 rotations.

Triple Double Upgrade

Upgrading into a TD Attack is possible but reduces stacking options.

• L>O Residue J>I 81.43% Perfect Clear chance, 3 solutions.

S>J

J>I

J>S

S>J

• O>L Residue S>L 66.03% Perfect Clear chance, 2 solutions, L>O 78.06% Perfect Clear chance, 8 solutions.

S>O

S>L

L>O

O>L

S>J

S>I

I>S

Perfect Clear

Stacking for a Tetris works for both T placements. It also provides a Perfect Clear chance after 8 Lines meaning one can use DPC Setups afterwards to return to a fresh bag.

• T>S/Z: 100% Perfect Clear chance, 72 unique solutions.

• S>T: 96.87% Perfect Clear chance, 55 unique solutions.

• Z>T: 94.68% Perfect Clear chance, 38 unique solutions.

See Also

Interchangeable Shapes