Block Out Level 871 Walkthrough: How to Clear the Board

To solve Level 871 in Block Out, your immediate priority is emptying a single column to create a working buffer. Starting the level with no free slots means you cannot sort colors freely until you create open space. Once you clear that first tube, use it strictly as a temporary transit slot to consolidate matching colors from the bottom up.

Step 1: Open Your First Empty Tube

Before making your first transfer, scan the board to identify which tube has the fewest color splits or holds surface blocks that can immediately transfer onto matching stacks elsewhere.

1. Find high-frequency top colors: Locate which matching color appears most often across the visible top layer.
2. Target one extraction tube: Pick the column that requires the fewest transfers to clear out completely. Shifting pieces across multiple columns without emptying one will rapidly lock the board.
3. Transfer matching tops: Move surface blocks onto matching colors that have open headroom in other tubes.
4. Uncover buried pairs: Prioritize moves that expose matching blocks beneath the surface rather than moves that merely rearrange top pieces.

Do not split matching block pairs to fill temporary gaps. Once you completely empty your chosen column, stop and evaluate the board before moving another piece.

Step 2: Consolidate Colors Through the Buffer

An open tube provides the mobility needed to access buried layers, but filling it permanently with mismatched blocks causes an immediate deadlock. Treat this slot as a staging ground.

When consolidating colors, build onto columns that already have matching bases. If a tube starts with two matching blocks at the bottom, direct identical blocks into that column until it reaches full capacity. Locking a completed color permanently removes it from the board, giving you fewer active elements to track.

Step 3: Prevent Mid-Game Deadlocks

Most failed attempts on Level 871 stem from careless single-block moves or miscalculating column capacity:

• Do not cap mixed bases: Never place an unrelated single block on top of a tube unless you have a confirmed follow-up move to clear it within two turns. Stacking unrelated single blocks over buried colors freezes those columns.
• Check receiving capacity: When transferring a connected group of matching blocks, confirm the destination tube has enough headroom to take the entire set. Moving only part of a grouped pair splits your resources and takes up space without clearing a column.
• Maintain the transit loop: When using the open tube to reach a buried block, execute the full sequence immediately: move the top piece into the transit tube, shift the revealed matching block to its target stack, and return the transit piece to an appropriate column.

Step 4: Execute the Endgame Sequence

Once three or four tubes are fully sorted and locked, the puzzle simplifies into a standard clearing cycle. Use your remaining open space to shift lingering surface pieces into their designated stacks. Keep your transit tube empty between individual transfers, work through the final split columns one color at a time, and fill the remaining tubes to clear Level 871.