FOUNDATIONS · LESSON 2 OF 5
Reading the queue
AFTER THIS GUIDEYou’ll be able to plan a pair of placements, use Hold to change their order and separate a visible piece from one you are only hoping for.
Give the next piece somewhere to go.
Looking ahead does not mean solving five pieces perfectly. Start with a pair: “this piece goes here, then that one can go there.” Before locking the first, picture the surface it leaves. If your second landing disappeared, revise the first decision.
NEXT shows upcoming pieces in order. Begin with the first preview; add a second when you can keep the first landing in mind. Five previews give information, not an obligation to memorise five moves.
Hold changes the order, not the supply.
With an empty Hold, storing the active piece brings in the first NEXT piece. With Hold occupied, the two pieces swap and the queue stays where it is. You cannot Hold again until you lock a piece. In Stacking Lab the default Hold key is Z; use your own binding if you changed it.
The trainer uses a seven-bag: one of each piece, shuffled, then another shuffled bag. The last I of one bag and first I of the next can be consecutive. If I is first in one bag and last in the next, twelve other pieces can appear between them. This describes the generated order before Hold reorders your placements.
You may infer what remains in a bag when you have tracked its boundary. You cannot assume that an arbitrary group of seven upcoming pieces contains one of everything. Use the visible queue first.
WORKED EXAMPLE · ACTIVE I, EMPTY HOLD, NEXT O → T
Let O prepare the I clear.
Use the same small board from the stacking lesson. I could go straight down the well now and clear the bottom two rows. That is legal. Here we compare a different plan: use the visible O first to make a four-row clear.
Read two jobs
The step in columns eight and nine needs O; the well needs I. I is active but O is next. Empty Hold lets you reverse those two placements.
Hold I, then place O
Press Hold once. O becomes active and I is stored. Drop O on the supported step. When O locks, T becomes active; Hold is available again.
Swap T for I
Hold again to bring back I and store T. The swap does not consume another NEXT piece. Rotate I vertically and drop it in the right well.
Make a new plan
The four rows clear. The next queued piece spawns, and T stays in Hold. Do not keep following the old plan: inspect the new board and the new preview.
What if O were not visible? “I will get an O eventually” would not justify waiting on this exact plan. The immediate two-line clear may be the better way to stay low. A plan needs available pieces and enough room to place them.
Common mistakes
Using Hold without reading what comes out
An empty Hold consumes the first preview; an occupied Hold does not. Say which piece will become active before pressing the key.
Looking far ahead while missing the next landing
If the first preview has nowhere safe to go after your move, five-piece memorisation will not fix it. Practise two connected placements first.
Treating the next bag as a rescue guarantee
A piece can still be several placements away. Extra height and extra dependencies matter while you wait. Take a smaller clear when it makes the remaining queue easier.
TAKE IT TO THE BOARD
14 pieces. Say the pair before the drop.
- Use 9–0, Gravity Off and NEXT 5. Play manually.
- For each of 14 placements, name a landing for the active piece and the first preview. You can change the plan after seeing the result.
- Before using Hold, say what comes out and whether NEXT advances. Check your prediction.
- If a pair fails, Undo and compare the first placement. Was the mistake the landing, the order, or an unseen piece you assumed would arrive?
What counts as progress? You can follow two placements without losing track of Hold. Count correct predictions, not how quickly you finish.
Open queue practice ↗Opens the mode. Set Gravity and NEXT yourself; your current settings are kept.
Keep these terms nearby
NEXT IN THIS PATH
Handling and finesse
Make your hands carry out the placement you already chose.
Read the next guide →Further reading
The Hold transitions and seven-bag examples here follow Stacking Lab’s implemented game rules. For broader game controls, see the official Tetris how-to-play page. Other editions, especially classic games, may use different randomisers or omit Hold.