Difference between revisions of "Secret Grade"

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ZL........
 
ZL........
 
ZLGGGGGGGG
 
ZLGGGGGGGG
ZLLG.GGGGG
+
ZLL.GGGGGG
 
</playfield>
 
</playfield>
 
Clearing the center row of vertical L "converts" it to the shape of the T in the notched setups. One must take care to ensure that the pieces used to clear the line do not interfere with forming the hole for that row.
 
Clearing the center row of vertical L "converts" it to the shape of the T in the notched setups. One must take care to ensure that the pieces used to clear the line do not interfere with forming the hole for that row.

Revision as of 04:19, 13 July 2009

"Secret Grade" is a hidden grading mechanism in the TGM series that rewards creating a ">" shape by leaving holes in the stack. At game over, the game evaluates the blocks in the field, looking for a zigzag pattern, and it awards a "secret grade" ranging from 9 to 1 for up to nine rows of the pattern completed, S1 to S9 for up to 18 rows, or Gm for all 19 rows.

Basic Strategy

Creating the correct holes in the stack is easier to accomplish when a "sawtooth" or "stairs" structure is maintained in the direction of the diagonal you are creating. By maintaining this structure, holes can be covered with others to finish holes and create the foundation for new ones. S, Z, and T are very useful for creating the sawtooth structure or covering holes, although any piece can be used to create useful structures.

         I
        II
       OOI
      SOOG
     SSGGG
    ISGGGG
   IIIGGGG
  TTGGGGGG
 TTGGGGGGG
         I
        II
       TTI
      TTGG
     ZZZZG
    OOGGGG
   JOOGGGG
  IJJJGGGG
 IIIGGGGGG
         I
        II
       JJI
      SJOO
     SSJOO
    ISGGGG
   IIIGGGG
  TTGGGGGG
 TTGGGGGGG

Line clears increment the level counter and can prevent progress. For these reasons, line clears are generally avoided. However, line clears can be useful or necessary in a variety of situations. Line clears are unavoidable when creating the first holes at either wall. If a line clear is necessary, holes can be built on top of the lines to be cleared and "dropped" into place.

   TT I
  TT IIILL
GGGGGGGGGL
GGGGGGGGGL
GGG GGGGGG
GG GGGGGGG
G GGGGGGGG
 GGGGGGGGG
   TT I
  TT IIILL
----------
----------
GGG GGGGGG
GG GGGGGGG
G GGGGGGGG
 GGGGGGGGG
   TT I
  TT IIILL
GGG GGGGGG
GG GGGGGGG
G GGGGGGGG
 GGGGGGGGG

Maintaining an even spread of pieces throughout the stack is very important. Uneven stacking can hinder the completion of holes and reduce placement choices near the top of the stack. Placement choices are limited near the top of the stack, so care should be taken to maintain an even stack without obstructions. If it appears that the stack is growing unstable, the best strategy is to clear lines or backtrack until a stable approach can be made.

Reaching the right wall is like starting over again; a line clear structure is needed to create the first few holes. Structures going to the right wall can be reused when returning to the left, but the pieces used must be flipped. For example, structures that used L before reaching the wall now use J on the return trip.

LLL    JJJ
L I    I J
 III  III


Starts

Starting the structure can be efficiently started with any piece but O. At least one line clear is required when using any other piece, but using O to create the first hole necessitates two.

LLL
L-I
-III
T-L
TTL
-TLL
L
L-
LL
-ZZZZ
I
II
I-
SS
-SS
J-
JJJL
-LLL
L
L-J
LLJ
-JJ

Starting line clears can also be used in the body of the building process. Try to use structures like these whenever a line clear appears to be necessary.

Other Line Clears

Some line clears can be useful in creating holes, but have little or no use as starting structures.


GGLLGGGGGG
GG LGGGGGG
G GLGGGGGG
 GGGGGGGGG


 I
IIIGGGGGGG
G GGGGGGGG
 GGGGGGGGG


Covers

GGG SGGGGG
GG SSGGGGG
G GSGGGGGG
 GGGGGGGGG

In the case that you have an open imperial cross or T shape, fill it with S/Z finish a hole and start another.


   TT
  TT
GGG SGGGGG
GG SSGGGGG
G GSGGGGGG
 GGGGGGGGG

Cover holes with S/Z to create the foundation for new holes.


   TT I
  TT III
GGG SGGGGG
GG SSGGGGG
G GSGGGGGG
 GGGGGGGGG

Place T next to this foundation to complete the hole and start a new one.

  SS
   SSGGGGG
G GGGGGGGG
 GGGGGGGGG
OOSS
OO SSGGGGG
G GGGGGGGG
 GGGGGGGGG

Keep an eye out for ways to create covers from the other side when you get pieces in a different order.
Covering with I can also be effective, but be wary when using L, J, or O; covering with these pieces can create unwanted hanging points or fill the space where you intend to form a hole.

GGG  GGGGG
GG JJGGGGG
G GJGGGGGG
 GGJGGGGGG
    GG  TT
   GGGZTTZ
  GGGGZ SZ
  GGGLZSSZ
GGGGGLZS Z
----------
GGGGGGGGG

Long pieces such as L, J, and I are effective at reaching into open spaces and finishing holes from the side. Fill open long crosses with L and J as you would fill open imperial crosses with S and Z. I can be used to complete holes in longer openings in a similar fashion.

Hangs

Hanging points are structures that impede the direct creation of holes; pieces must instead be placed in so they are "hanging" from this structure in order to create a hole. Using O, L, or J to cover a hole have the highest potential for creating hanging points. A line clear may be necessary to continue, but sometimes "hanging" structures can be useful in quickly creating multiple holes with few pieces.
If the structure is 3 units tall, only L/J can be hung from the structure and complete a hole, making a line clear the best strategy.

  LL
  JL
GGJL GGGGG
GJJ GGGGGG
GG GGGGGGG
G GGGGGGGG
 GGGGGGGGG
  LL S
GGJLSSGGGG
GGJLSGGGGG
GJJ GGGGGG
GG GGGGGGG
G GGGGGGGG
 GGGGGGGGG
  LL S
GJJ GGGGGG
GG GGGGGGG
G GGGGGGGG
 GGGGGGGGG


If the structure is 2 units tall, all pieces but I can be hung from the structure to complete a hole. A few pieces will maintain the 2 unit structure, while a few will necessitate a line clear. T can successfully end the hanging structure without requiring a line clear.

  LLL
SSLTIII GG
ZSSTTI GGG
ZJJJT GGGG
ZOOJ GGGGG
ZOO GGGGGG
GG GGGGGGG
G GGGGGGGG
 GGGGGGGGG

In this diagram, O starts the structure and J and S maintain it. Z and L could have been used to end the structure by clearing a line, but T caps off the structure without a clear.

Finishes

There are very few ways to complete the pattern. The 19th hole must be covered in order to qualify for the Gm grade. For this reason, the successful completion of the pattern is dependent on receiving specific pieces depending on the current state of the stack.

The safest way to finish the pattern is to cover the sawtooth at the top with a Z, simultaneously finishing holes 18 and 19. After placing the Z, you can then proceed to fill the rest of row 19.

Riskier methods will depend on receiving one or more I blocks precisely when they are needed. An I block can spawn and move freely in row 20, enabling it to be used as a cover for the incomplete pattern.

An even riskier method involves placing a T flat over hole 18, clearing row 19, and covering hole 19 with a J.

Keep in mind that the piece that causes the game to end can also complete the pattern.

SS
 SSGGGGGGG
G GGGGGGGG
GG GGGGGGG
GGG GGGGGG
GGGG GGGGG
GGGGG GGGG
GGGGGG GGG
GGGGGGG GG
GGGGGGGG G
GGGGGGGGG
GGGGGGGG G
GGGGGGG GG
GGGGGG GGG
GGGGG GGGG
GGGG GGGGG
GGG GGGGGG
GG GGGGGGG
G GGGGGGGG
 GGGGGGGGG
ZZZZ
 GGGGGGGGG
G GGGGGGGG
GG GGGGGGG
GGG GGGGGG
GGGG GGGGG
GGGGG GGGG
GGGGGG GGG
GGGGGGG GG
GGGGGGGG G
GGGGGGGGG
GGGGGGGG G
GGGGGGG GG
GGGGGG GGG
GGGGG GGGG
GGGG GGGGG
GGG GGGGGG
GG GGGGGGG
G GGGGGGGG
 GGGGGGGGG
 I
IIIZZZZGGG
G GGGGGGGG
GG GGGGGGG
GGG GGGGGG
GGGG GGGGG
GGGGG GGGG
GGGGGG GGG
GGGGGGG GG
GGGGGGGG G
GGGGGGGGG
GGGGGGGG G
GGGGGGG GG
GGGGGG GGG
GGGGG GGGG
GGGG GGGGG
GGG GGGGGG
GG GGGGGGG
G GGGGGGGG
 GGGGGGGGG
JJJ TT LOO
 IJTTLLLOO
G GGGGGGGG
GG GGGGGGG
GGG GGGGGG
GGGG GGGGG
GGGGG GGGG
GGGGGG GGG
GGGGGGG GG
GGGGGGGG G
GGGGGGGGG
GGGGGGGG G
GGGGGGG GG
GGGGGG GGG
GGGGG GGGG
GGGG GGGGG
GGG GGGGGG
GG GGGGGGG
G GGGGGGGG
 GGGGGGGGG

When making considerations for a potential GM solution, it may be advantageous to place L, J, and I blocks vertically on the right side of the field as you approach the top of the field. Several vertical placements of these pieces will work in parallel to fill multiple rows while leaving the spawn area open for new pieces. On the other hand, horizontal placements in the center or on the left may reduce mobility or occupy part of the spawn area.

BBBBBBLLBB
SS ----LJZ
 SS--- LJZ
G IIIOOJJZ
GG IGOOGGZ
GGG GGGGGG
GGGG GGGGG
GGGGG GGGG
GGGGGG GGG
GGGGGGG GG
GGGGGGGG G


Here are a few examples of viable finishes:

..........
..........
I.........
II........
IGG.GGGGGG
..........
Z.........
ZI........
ZII.......
ZIGG.GGGGG

These setups require a notch on the left side for the T. You can use a vertical I-block as a spacer to use this setup one row lower than normal.

..........
Z.........
ZL........
ZLGGGGGGGG
ZLL.GGGGGG

Clearing the center row of vertical L "converts" it to the shape of the T in the notched setups. One must take care to ensure that the pieces used to clear the line do not interfere with forming the hole for that row.