How to Build a Quad
A quad clears four lines at once and is the single highest-scoring move in the game. The method fits in one sentence: leave one column open, stack four rows on the rest, and drop the I-piece in. The hard part is keeping the board from collapsing while you wait, and half of this guide is about that.
The Numbers: Why Quads Pay Off
Base scores per clear (level 1): single 100, double 250, triple 450, quad 700. Comparing four ways to clear four lines:
| Method | Base pts | vs Quad |
|---|---|---|
| 4 singles | 400 pts | 57% |
| 2 doubles | 500 pts | 71% |
| Triple + single | 550 pts | 79% |
| 1 quad | 700 pts | 100% |
With combo bonuses the gap widens further. But the table hides one cost: while you hold four rows un-cleared, the well is four rows taller. Failing to manage that risk means losing 700 points and the entire game.
Which Column to Leave Open
Use column 1 or column 9 — an edge. Opening an edge leaves the remaining eight cells as one connected flat area where any piece can fit. Opening column 5 (the center) splits the surface into left-four and right-four, each needing independent management and limiting where the O-piece and I-piece (horizontal) can go.
In a 9-column well this matters even more. A 10-column well minus one edge leaves nine cells; here it leaves eight. Eight is a convenient even number: two O-pieces fill a row, or one O-piece and one T-piece plus a J or L. In practice, eight-cell rows complete cleanly with two or three pieces.
- Open column
- Filled rows
When Will the I-Piece Arrive? Wait Limit Math
Pieces are not fully random. Seven types are shuffled into a bag, dealt in order, then reshuffled. Within any seven consecutive pieces the I-piece always appears exactly once. This guarantee makes quad strategy a calculated wait, not a gamble.
Worst case: if the I-piece was the first of the previous bag and the last of the next, 12 other pieces separate the two I-pieces. Twelve pieces generate roughly six eight-cell rows. Adding four rows to the existing well plus those six rows of pieces approaches dangerous height.
The practical rule: if the next preview does not show the I-piece, your total height exceeds row 12, and you already have four rows ready — clear three of them as a triple. A triple is 64% of a quad, but a topped-out game scores zero. Making this call on time matters more than building the quad itself.
Five Steps to Build a Quad
- 1Choose one column to leave open
Pick column 1 or 9 (an edge). Opening the center splits the remaining eight cells into two separate zones of four, making surface management much harder. - 2Raise the other eight columns to the same height
Fill rows across the eight columns one at a time. Keep height differences within one cell so any piece can find a spot. - 3Stack four eight-cell rows
When four rows are complete except for the open column, the setup is ready. This state is commonly called 'digging the well.' - 4Drop the I-piece vertically into the open column
Rotate the I-piece upright and drop it into the open column. Four rows complete simultaneously and disappear. This is a quad. - 5Bail before it collapses
If you have three rows ready but no I-piece in sight and total height exceeds row 12, abandon the quad. Fill the open column with a T or J/L piece and settle for a double or triple.
One more thing: when the I-piece arrives and the well is only two rows deep, you do not have to use it immediately. You can lay it flat elsewhere and wait for the next one — but only if height is comfortable. Past row 12, use whatever I-piece you get.
Quad FAQ
Q. How much better is a quad, exactly?
At level 1 a quad is 700 points; four singles total 400 — a 1.75x difference. Since the level multiplies scores, at level 5 the gap is 3,500 vs 2,000, five times larger in absolute terms.
Q. How long until the I-piece arrives?
Pieces come in shuffled bags of seven, so every bag contains exactly one I-piece. Best case: the very next piece. Worst case: 12 pieces later (last of the previous bag, then first of this bag was also I).
Q. Why not open the center column?
Opening the center splits the remaining eight cells into left-four and right-four, forcing you to manage two separate surfaces. Opening an edge column leaves all eight cells connected, which is much easier.
Q. I accidentally placed a block in the quad column.
Do not try to dig it out. Clearing the rows above it destroys your four-row setup entirely. Instead, abandon that column and designate the adjacent column as your new quad well. The loss is smaller.
Q. Is there a bonus for consecutive quads?
Yes. Any clear that immediately follows another clear triggers the combo bonus: 50 points on the second, 100 on the third, etc., each multiplied by level. Back-to-back quads earn the combo bonus on top of the base 700 each.
Q. Should I give up on quads at high levels?
Past level 10, natural drop speed falls below 0.2 seconds and maintaining a four-row well becomes risky. Frequent doubles and triples that keep the combo alive tend to outscore isolated quads at those speeds.