THE IDEA: KEEP THE NUMBERS THAT ADD UP
Every row has a target number on its right; every column has one along the bottom. The grid starts completely full. You go through and cross out the numbers you don't want, so that the ones you keep in each row add up to that row's target — and the ones you keep in each column add up to that column's target. Get every row and every column right at the same time and you've solved it.
That's the entire game. Two things to hold:
- Kept numbers in a line must total its target. Cross out the rest.
- Rows and columns share cells. A number you keep for a row also counts toward its column — so the two keep each other honest.
And the best opening move needs no adding at all — just a number that's obviously too big.
LET'S ACTUALLY SOLVE ONE — STEP BY STEP
Here's a real Sumplete. Grid full of numbers, a target beside every row and under every column. Don't panic at the wall of digits — we only ever look at one line at a time.
The starting grid — every cell full, a target on each row and column.
Step 1 — a number bigger than the target can't stay.
Look at the top row. It has to total 5 — but sitting right there is a 6. A single number bigger than the whole target can never be part of the answer (keeping it already overshoots on its own). So cross the 6 out, no adding required. Hunt these first: any number larger than its row or column target is a free delete.
Step 2 — and some numbers simply can't be deleted.
The bottom row is 7, 7, 9, 7 and needs 23. Try crossing out the 9: the three 7s left only make 21 — short. So the 9 can't go; it has to stay. That means one of the three 7s gets crossed instead… but which one? The row alone can't tell us. Time to bring in a column.
Step 3 — the column breaks the tie.
Look down the left column: 1, 2, 3, 7, target 6. There's our too-big trick again — the 7 alone beats 6, so it's gone. And here's the lovely part: that 7 is the very one in the bottom row. The column just answered the row's question. This row-and-column tag-team is the heart of Sumplete.
From here it tumbles. With that 7 crossed, the bottom row's remaining numbers must all be kept to reach 23 — and each cross you make squeezes a row or column until its leftovers are forced. Keep chaining: a too-big delete here, a "must total exactly the target" there.
Cascading — the third row already holds its 3 and needs just 6 more, so its 7 can't stay either. Each cross forces the next.
Done. Add up the survivors in any row or column — it lands on the target every time. 👻
THE THREE MOVES, IN ORDER
Almost every Sumplete falls to the same little loop:
- Too big → cross out. Any number larger than what its row or column still needs can't be kept. Free deletes — start here.
- Can't-lose → keep. If deleting a number leaves the rest of the line short of the target, that number has to stay.
- Line's done → finish it. Once a row or column already hits its target, cross out everything still undecided in it. And when the kept-so-far plus the leftovers land exactly on the target, keep them all.
Stuck on a line? Switch to the column (or row) that crosses it — the shared cell almost always gives you the next move. Never a guess: every cross and every keep has a number-sized reason behind it.
THAT'S IT — GO DO ONE
Spot the too-big numbers, cross them out, keep the ones you can't live without, and let the rows and columns trade hints until the grid clicks shut. The first time a single cross-out cascades through half the board, you'll get why people find this one so soothing — no words, no maths homework, no ads in the middle of your puzzle, just you, a grid of numbers, and a ghost who's quietly chuffed when the last one lands.