Skims are non-Tetris and non-T-spin line clears that shape the field, making it safer, cleaner, more balanced, or more convenient to build other setups.

One might ask: Hey, skimming involves breaking back-to-back bonuses! It also involves upstacking only to get down without having done a Tetris or T-spin!

Hence, they must be inefficient!

However, when used by a skilled Tetris player, they massively increase one’s offense and defense.

And guess what? It takes only a few minutes of reading this chapter to apply it to your game! An instant Tetris extraordinaire!

Making Skims Your Allies

Here is how to use skims to vastly improve your survivability and firepower:

1. Skim to Avoid the Dreaded I-Dependencies

Many casual Tetris players stack until they reach this tragic mound:

Diagram Set 6-1
A

The green-circled part has a massive I-dependency.

This often happens when you place the main Tetris hole in the most extreme column (often columns 1 or 10).

The far-left (in the green circle) contains an I-dependency. This means you must fill it with an I piece, like in the following, to even it out. This uses many I pieces:

Diagram Set 6-2
A

Placing the first I in the stack creates a super-clean hole in column 1, which can lead to excessive I dependencies.

However, you may not get enough I pieces to do this. Hence, you run the risk of getting into this situation:

Diagram Set 6-3
1	2

The player mindlessly upstacks the lavender parts. The left side has a severe I-dependency in column 2.

He balances the stack by putting 2 Is on the left side. However, he runs out of I pieces to make a Tetris line clear, making him vulnerable to being attacked with no defenses!

Here, the player wastes too many I pieces in the stack to stabilize and balance it. However, they do not get enough Is to make the actual Tetris line clear in column 1’s hole! Hence, they may get topped out.

In Classic Tetris, this is deadly.

Hence, what can one do in this situation? Simple! You skim like this:

Diagram Set 6-4
1	2

The player skims with the Z, Z, J, O, and L pieces to get down to safety.

The field has been safely lowered. The I-dependency on the left side has been eliminated.

With the right skims, the player can then rebalance the stack again to enlarge the top, stacking area, making it safer to build.

2. Mid-Lane Troubles

When your central Tetris hole is somewhere in the middle columns, you may apply the last section’s methods to skim and balance the stack, too.

Here is an example:

Diagram Set 6-5
A1	B1

C1

Mid-lane scenarios with imbalanced stacks on both sides. A1, B1, and C1 lead to A2, B2, and C2 respectively in the following diagram.

Here, the player has a dreadful 2-block-wide well in the middle. This leads to many I-dependencies. Without extra Is, the player may get into danger.

Hence, they may skim this way with other pieces:

Diagram Set 6-6
A2	B2

C2

Ways of resolving the last diagram set’s imbalanced stack scenarios, while mid-laning.

This balances the field, making stacking safer.

3. The Ts Love Skims

Skims also open up another trick: they let you create fancy little setups called T-spins to boost your firepower.

I will cover T-spins in depth later. They are simply T-shaped cavities that let you soft-drop a T piece into them. When you rotate the T and get a line clear, you send extra garbage to the opponent.

You may return to this section later, after reading this book’s T-spin chapter, to review this portion.

Here is how to apply this technique:

Diagram Set 6-7
1	2

The player uses a T-skim to create a single. This balances both sides of the stack, allowing a T-spin follow-up.

Diagram Set 6-8
1	2

Same, with an L skim leading to an easy T-spin.

Here, the player has an imbalanced stack, with the central Tetris hole in the middle columns.

However, they skim with various pieces, resulting in a balanced field (both the left and right stacks are of even height).

They can then place a simple piece (often with S and Z pieces) to make an overhang to ready the T-spin.

This enables skims to become one’s ally!

In a Nutshell

Skims vastly improve your mid-game versatility and survivability. They also create many ways to boost firepower by making T-spins.

Summary

Skim to reduce or avoid I-piece dependencies, especially during 9-0 stacking. When the main Tetris hole is in the mid-lane, skims can fix an imbalanced stack. Skims can help you make mid-lane T-spins easily.