You know the rules: a 6×6 grid, digits 1 through 6, every row, column, and 2×3 block complete without repeats, plus dotted cages whose digits sum to the label and never duplicate inside the cage. ProPuz Mini Killer starts with an empty grid—no givens—so the opening moves come entirely from technique, not from lucky starter digits. This page is your first structured toolkit: five moves you can run on every Easy board before you reach for harder arithmetic. If you need a rules refresher first, read basic rules explained; if you prefer narrative tips, pair this with beginner tips.
Technique 1: the small-cage inventory
Before you type anything, walk the board and classify cages by constraint strength. Two-cell cages with extreme sums—3, 4, 10, 11—have tiny menus. Three-cell cages summing to 6 or 15 are equally rigid. Mark these mentally as “hot” cages. A cage inventory takes thirty seconds and prevents the most common beginner stall: filling a wide row while a corner cage already decided half the digits.
On ProPuz Easy boards, the inventory often reveals one or two cages with only a single legal combination. That is your entry point. Do not hunt for the prettiest empty cell; hunt for the cage with the fewest options. Difficulty tiers from Easy through Expert all reward this habit—Expert just hides the hotspots behind more overlapping cages.
Technique 2: tight combination recognition
Once you know which cages are hot, list their legal digit sets. A two-cell cage of sum 7 allows {1, 6}, {2, 5}, or {3, 4}—three pairs, still manageable. Sum 11 allows only {5, 6}. Sum 3 allows only {1, 2}. You do not need every sum memorized on day one; learn the endpoints and build outward. When a combination is unique, treat the cage as a locked set even before you know which digit goes in which cell.
Tight combinations propagate: if a cage forces {5, 6} and one cell sits in a row that already contains 5, the partner must be 6. That single elimination often unlocks a block single elsewhere. For a deeper dive into menus and listing methods, see cage sums and combinations.
Technique 3: block singles
Mini Killer uses 2×3 blocks, not 3×3 boxes. Solvers coming from 9×9 Sudoku or full Killer sometimes forget blocks until Check fails. A block single appears when five of six digits are placed in a block and exactly one empty cell remains—that cell must hold the missing digit. Cage logic often fills four digits across a block without you noticing; the fifth placement creates an instant single.
After every cage-driven fill, scan the containing block. Ask: “Which digit is still missing here?” Block singles are quieter than row singles because cages draw your eye along dotted outlines instead of rectangular regions. Naming “block check” after each placement builds the reflex faster than hoping you will remember later.
Technique 4: leftover singles in rows and columns
When cage work and block scans stall, pivot to unit leftovers. A row with five digits placed has only one legal option for the empty cell—provided cage rules still permit that digit. Always verify the cage side: a row single of 4 is useless if the cage already contains 4 or if 4 would break the remaining sum budget.
Leftover singles often appear late in Easy puzzles after cage combinations have distributed digits across the grid. They feel like Sudoku proper, but Mini Killer never lets you forget cages—run the triple check (row, column, block, then cage sum and cage uniqueness) before committing. One illegal leftover undo wastes more time than the scan saves.
Technique 5: the scan loop
Wrap the four moves above into a loop you repeat until the grid fills or you genuinely need notes. Pass one: cage inventory and tight combinations. Pass two: block singles anywhere they appear. Pass three: row and column leftovers with cage verification. Pass four: return to cages—partial fills change remaining sums and may shrink combination menus. This loop is the backbone of 6×6 step-by-step solving.
Do not exit the loop early because one row “looks done.” Incomplete cages touching that row may still constrain neighbors. When a full loop yields zero progress, that is your signal to add pencil marks—not to guess. See pencil marks for Mini Killer for when notes earn their keep.
How the toolkit fits ProPuz practice
Run all five techniques on Easy until a full board finishes with explainable logic and minimal Check rescue. ProPuz offers Medium, Hard, and Expert when combination menus widen and cages overlap more aggressively—but the scan loop stays the same; only the bookkeeping load increases. Use daily challenges for variety without jumping tiers prematurely.
Avoid the habits cataloged in common mistakes: repeating digits inside cages, ignoring blocks, and guessing on empty starts. When you want speed without sacrificing the loop, read best strategies for faster solving. When you want a logic-only mindset before Medium, see solve without guessing.
Closing the first toolkit
Mini Killer on ProPuz rewards systematic scanning over inspiration. Inventory small cages, recognize tight combinations, harvest block singles, clean up row and column leftovers, and loop until the grid speaks. Six digits and compact blocks make the board feel friendly; dual constraints make sloppy scanning expensive. Master this toolkit on Easy and every higher tier becomes a matter of wider menus, not new magic.
Browse the full article library, skim how to play, or open an Easy puzzle and run the scan loop on a live empty-start grid.