Tetris Wiki

Skimming is a clearing method by which a player can use to make a stack even. Skimming is done by placing a tetromino either at the edge or at the surface of a stack and cleaing a line as a result. The technique is favorable in multiplayer tetris because it can save a player from topping out, flatten the field, or allow a player to tetris.

Skimming is especially effective in games that use combo scoring. In other games, skimming forfeits "back-to-back" bonuses and is penalized with more line clear delay per line.

Minimize I tetromino dependence[]

When a player is starved of I tetrominoes, they have to depend on other tetrominoes to keep themself from topping out or to keep their field stable.

GGGGGGGG
GGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGG
GGGGGGGGLL
GGGGGGGGGL
GGGGGGGGGL
GGGGGGGGG
GGGGGGGGG
GGGGGGGGOO
GGGGGGGGOO
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGS
GGGGGGGGSS
GGGGGGGGGS
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGJJJ
GGGGGGGGGJ
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG

A T can be used to skim, either directly or by creating an overhang to a T-Spin Double.

GGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGTTT
GGGGGGGGTG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG

Funnel[]

A field may not be set up for skimming without covering the open column. Stack around the open column to create a funnel for skimming efficiently. A funnel may be created by filling up the necessary cells to create the indent.

GGG-----
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
OOJ
GGGOOJJJ
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG

If there is already an indent, fill up the cells to create the wall.

GG--GGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
ZZ
GGZZGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG

Inverted Funnel[]

Funnels don't have to be limited to long and empty single columns.

GGGG--GG
GGGG--GG
GGGGGGGG
GGGGGGGGG
GGGGOOGG
GGGGOOGG
GGGGGGGG
GGGGGGGGG
GGGGGGGG
GGGGGGGG
GGGGGGGG
GGGGGGGG
GGGGGGGG
GGGGGGGG
GGGGGGGG
GGGGSGGGG
GGGGSSGGGG
GGGGSGGGG
GGGGGGGG
GGGGGGGG
GGGGSGGGG
GGGGSGGGG

Line Clear[]

A line clear can be used to create a funnel. In this example, using an L to clear the far right column will not result in a funnel. If an I was to be used instead, a JZ funnel will be created.

GGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
I
GGGGGGGI
GGGGGGGGGI
GGGGGGGGGI
GGGGGGGGG
GGGGGGGGG
I
GGGGGGGI
GGGGGGGGG
GGGGGGGGG
GGGGGGGG
GGGGGGGG
GGGGGGGG
GGGGGGGG
GGGGGGGG
GGGGGGGGLL
GGGGGGGGL
GGGGGGGGL
GGGGGGGG
GGGGGGGGL
GGGGGGGGL

Tetrominos can create different funnels depending on their orientation when used to clear a line.

GGGGGGG
GGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGJJJ
GGGGGGGJ
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGG
GGGGGGGJ
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGG
GGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGJ
GGGGGGGJJJ
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGG
GGGGGGGJ
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGG
GGGGGGGG
GGGGGGGG
GGGGGGGG
GGGGGGGG
GGGGGGGGLL
GGGGGGGGL
GGGGGGGGL
GGGGGGGG
GGGGGGGGL
GGGGGGGGL
GGGGGGGG
GGGGGGGG
GGGGGGGG
GGGGGGGG
GGGGGGGG
GGGGGGGGL
GGGGGGGGL
GGGGGGGGLL
GGGGGGGG
GGGGGGGGL
GGGGGGGGL

Different tetrominoes can create the same funnel depending on their orientation when used to clear a line.

GGGGGGG
GGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGJ
GGGGGGGJJJ
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGJ
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGG
GGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGLLL
GGGGGGGL
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGL
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGG
GGGGGGGG
GGGGGGGG
GGGGGGGG
GGGGGGGG
GGGGGGGGJ
GGGGGGGGJ
GGGGGGGGJJ
GGGGGGGG
GGGGGGGGLL
GGGGGGGGL
GGGGGGGGL
GGGGGGGG
GGGGGGGGT
GGGGGGGGTT
GGGGGGGGT

Overhang[]

Funnels can be formed by rotating tetrominoes under overhangs.

GGGGGGGG
GGGGGGGG
GGGGGGG
GGGGGGGG
GGGGGGGGG
GGGGGGGG
GGGGGGGGT
GGGGGGGTT
GGGGGGGGT
GGGGGGGGG
GGGGGGGG
GGGGGGGG
GGGGGGGTTT
GGGGGGGGT
GGGGGGGGG
GGGGGGGG
GGGGGGGGT
GGGGGGGTT
GGGGGGGGT
GGGGGGGGG
GGGGGGGG
GGGGGGG
GGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGT
GGGGGGGTT
GGGGGGGGT
GGGGGGGGG
GGGGGGGGG
GGGGGGGG
GGGGGGGTTT
GGGGGGGGT
GGGGGGGGG
GGGGGGGGG
GGGGGGGG
GGGGGGGGT
GGGGGGGGG
GGGGGGGGG
GGGGGGGG
GGGGGGG
GGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGZ
GGGGGGGZZ
GGGGGGGGZ
GGGGGGGGG
GGGGGGGGG
GGGGGGGG
GGGGGGGZZ
GGGGGGGGZZ
GGGGGGGGG
GGGGGGGGG
GGGGGGGG
GGGGGGGZZ
GGGGGGGGG
GGGGGGGGG

This only works in SRS.

GGGGGGGG
GGGGGGGG
GGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGG
GGGGGGGGS
GGGGGGGSS
GGGGGGGGGS
GGGGGGGGG
GGGGGGGG
GGGGGGGGSS
GGGGGGGSS
GGGGGGGGG
GGGGGGGGG
GGGGGGGG
GGGGGGGSS
GGGGGGGGG
GGGGGGGGG

This only works in ARS.

GGGGGGGG
GGGGGGGG
GGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGI
GGGGGGGGII
GGGGGGGI
GGGGGGGGG
GGGGGGGGG
GGGGGGGG
GGGGGGGGI
GGGGGGGIII
GGGGGGGGG
GGGGGGGGG
GGGGGGGG
GGGGGGGGI
GGGGGGGGG
GGGGGGGGG

This works only in SRS with the exception of TGM3's Classic rotation system (an ARS variant), where the T is given a floor kick.

GGGGGGGG
GGGGGGGG
GGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGG
GGGGGGGGT
GGGGGGGTT
GGGGGGGGGT
GGGGGGGGG
GGGGGGGG
GGGGGGGGT
GGGGGGGTTT
GGGGGGGGG
GGGGGGGGG
GGGGGGGG
GGGGGGGGT
GGGGGGGGG
GGGGGGGGG

Twist[]

Twists may be used to create funnels.

GGGGGGGG
GGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGT
GGGGGGGTT
GGGGGGGGTG
GGGGGGGGG
GGGGGGGGG
GGGGGGGG
GGGGGGGPPP
GGGGGGGGPG
GGGGGGGGG
GGGGGGGGG
GGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGG
GGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGT
GGGGGGTT
GGGGGGGTGG
GGGGGGGGG
GGGGGGGGG
GGGGGGG
GGGGGGTTT
GGGGGGGTGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGP
GGGGGGPP
GGGGGGGPGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGT
GGGGGGTT
GGGGGGGGG
GGGGGGGGG

These only work in SRS.

GGGGGGGG
GGGGGGGG
GGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGJ
GGGGGGGGJ
GGGGGGGJJ
GGGGGGGGG
GGGGGGGGG
GGGGGGGG
GGGGGGGG
GGGGGGGJJJ
GGGGGGGGGJ
GGGGGGGGG
GGGGGGGG
GGGGGGGG
GGGGGGGGG
GGGGGGG
GGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGT
GGGGGGGTTT
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGP
GGGGGGGPP
GGGGGGGPGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGT
GGGGGGGTT
GGGGGGGGG
GGGGGGGGG
GGGGGGG
GGGGGGG
GGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGT
GGGGGGGTTT
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGP
GGGGGGGPP
GGGGGGGGGP
GGGGGGGGG
GGGGGGGGG
GGGGGGGT
GGGGGGGTT
GGGGGGGGG
GGGGGGGGG

Alternative Funnel[]

Funnels can be set up without utilizing the open column.

GGGGGGG
GGGGGGG
GGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGZ
GGGGGGGZZ
GGGGGGGZ
GGGGGGGGG
GGGGGGGGG
GGGGGGGJJZ
GGGGGGGJZZ
GGGGGGGJZ
GGGGGGGGG
GGGGGGGGG
GGGGGGG
GGGGGGG
GGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGG
GGGGGGGSS
GGGGGGGSS
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGLLL
GGGGGGGLSS
GGGGGGGSS
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGG
GGGGGG
GGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGG
GGGGGGOO
GGGGGGGOO
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGS
GGGGGGSSOO
GGGGGGGSOO
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG

Suspended Funnel[]

Funnels can be extended over a column.

GGGGGG
GGGGGGG
GGGGGGGGG
GGGGGGGG
GGGGGG
GGGGGGGJJJ
GGGGGGGGGJ
GGGGGGGG
GGGGGG
GGGGGGG
GGGGGGGGG
GGGGGGGG
GGGGGGZZ
GGGGGGGZZ
GGGGGGGGG
GGGGGGGG
GGGGGGZZLL
GGGGGGGZZL
GGGGGGGGGL
GGGGGGGG
GGGGGGG
GGGGGGG
GGGGGGGG
GGGGGGGG
GGGGGGGS
GGGGGGGSS
GGGGGGGGS
GGGGGGGG
GGGGGGGSLL
GGGGGGGSSL
GGGGGGGGSL
GGGGGGGG
GGGGGGG
GGGGGGG
GGGGGGGOO
GGGGGGGOO
GGGGGGGG
GGGGGGG
GGGGGGGJJJ
GGGGGGGOOJ
GGGGGGGOO
GGGGGGGG
GGGGGGGJJJ
GGGGGGGOOJ
GGGGGGGG
GGGGGGG
GGGGGGG
GGGGGGGOO
GGGGGGGOO
GGGGGGGG
GGGGGGG
GGGGGGGLL
GGGGGGGOOL
GGGGGGGOOL
GGGGGGGG
GGGGGGGLLL
GGGGGGGLLL
GGGGGGGG

Alternate[]

Funnels can be mirrored with various line clears that raise the wall on the opposite side.

GGGGGG
GGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGZZ
GGGGGGGZZG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGZZ
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGG
GGGGGGGG
GGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGT
GGGGGGGGTT
GGGGGGGGT
GGGGGGGGG
GGGGGGGGG
GGGGGGGT
GGGGGGGGT
GGGGGGGGG
GGGGGGGGG
GGGGGGG
GGGGGGGG
GGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGJ
GGGGGGGGJ
GGGGGGGGJJ
GGGGGGGGG
GGGGGGGGG
GGGGGGGJ
GGGGGGGGJ
GGGGGGGGG
GGGGGGGGG

The concept can be taken further. In this example, the S tetromino can convert the LS funnel into a JZ funnel. The process may be repeated until the wall on either side of the funnel becomes too short to skim any further.

GGGGGGG
GGGGGGG
GGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGG
GGGGGGGS
GGGGGGGSSG
GGGGGGGGSG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGG
GGGGGGGS
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGZ
GGGGGGGSZZ
GGGGGGGGZG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGZ
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
S
GGGGGGGSSZ
GGGGGGGGSG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG

Inverted funnels can be mirrored efficiently with a J/L or T tetromino.

GGGGGGGG
GGGGGGGG
GGGGGGGG
GGGGGGGG
GGGGGGGGG
GGGGGGGG
GGGGGGGG
GGGGGGGGLL
GGGGGGGGL
GGGGGGGGGL
GGGGGGGG
GGGGGGGG
GGGGGGGGL
GGGGGGGG
GGGGGGGG
GGGGGGGG
GGGGGGGG
GGGGGGGGG
GGGGGGGG
GGGGGGGG
GGGGGGGGT
GGGGGGGGTT
GGGGGGGGGT
GGGGGGGG
GGGGGGGG
GGGGGGGGT

Fill[]

When unable to tetris because of a funnel, fill it up. The main idea is to fill up more rows than the amount you clear. Technically, the I tetromino would be the best choice since it clears no rows, but it requires the player to have another I tetromino on hand. Therefore, the next best choices are the L, the J, and the T because they clear only one row for every 2 they complete. The S/Z tetromino clears two rows for every two rows it completes, which cancels out any effects.

GGGGGGGG
GGGGGGGG
GGGGGGGG
GGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGG
GGGGGGGGL
GGGGGGGGL
GGGGGGGGLL
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGG
GGGGGGGGJJ
GGGGGGGGJ
GGGGGGGGJ
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGG
GGGGGGGGT
GGGGGGGGTT
GGGGGGGGT
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG

Flatten[]

Step pyramid and castle structures may become an obstacle when stacking for a tetris. Only specific tetrominos can fit, which limits a player's placement options. Minor line clears can be performed to flatten the structures.

GGGGGG
GGGGGG
GGGGGGG
GGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGG
GGGGGG
GGGGGGGZZ
GGGGGGGGZZ
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGG
GGGGGG
GGGGGGGTTT
GGGGGGGGT
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGG
GGGGGG
GGGGGGG
GGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGG
GGGGGG
GGGGGGGLLL
GGGGGGGLG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGG
GGGGGG
GGGGGGGLG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG

Order[]

When skimming consecutively, the order in which tetrominoes are used can make a difference. Tetromino properties have to be considered.

In this situation, clearing with an S first eliminates the funnel, disallowing any further skimming without covering the open column.

GGGGGGGG
GGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGS
GGGGGGGGSS
GGGGGGGGGS
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
LL
GGGGGGGGSL
GGGGGGGGGL
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG

Instead, if an L was to be used first, the funnel would still exist.

GGGGGGGG
GGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGG
GGGGGGGGLL
GGGGGGGGGL
GGGGGGGGGL
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
S
GGGGGGGGSS
GGGGGGGGGS
GGGGGGGGG
GGGGGGGGG

The same principle also applies to inverted funnels. In this example, clearing with a T first takes away the opportunity of skimming with an L.

GGGGGGGG
GGGGGGGG
GGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGG
GGGGGGTGG
GGGGGGTTGG
GGGGGGGTGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGG
GGGGGGTGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG

If the L was to be used first, the funnel would still be able to accomodate the T.

GGGGGGGG
GGGGGGGG
GGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGG
GGGGGGLLGG
GGGGGGLGG
GGGGGGGLGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG
T
GGGGGGTTGG
GGGGGGTLGG
GGGGGGGGG
GGGGGGGGG
GGGGGGGGG