Learn surface Go

Click the marked point or use Pass when prompted. Some exercises ask you to try an illegal move and observe its rejection. Select stones to inspect their chains and liberties.

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Recorded actions for this exercise

Keep these rules together

Connection: Use actual neighboring points, including every seam. Diagonal contact does not connect stones.
Capture: Remove opposing chains with no liberties, then reject suicide. Shared liberties count once.
Repetition: A placement may not repeat any complete earlier board coloring. A fresh diagram study knows only the history recorded from that setup.
Finish: Two consecutive passes end the branch. Score the actual remaining stones and exclusively bordered empty regions; add White’s fixed komi. There is no automatic dead-stone removal.

The +0.5 default komi is an experimental tie-break. These variants have no established balanced komi. Study outcomes remain study outcomes.

Files are a–i, including i. I:d5 and II:d5 identify different points. Arrow keys follow actual adjacency; Page Up or Page Down switches panels. Enter or Space selects the focused point, and Escape clears inspection.

Connections in the three boards

Black stones at i3 and a9 form one highlighted chain across the Möbius side seam, with six distinct liberties. — **Möbius**After Black a9, the stones at i3 and a9 belong to one chain. The side connection reflects rank 3 to rank 9.

Black stones at e18 and e1 are connected through the Klein board’s top-to-bottom wrap, with their six liberties highlighted. — **Klein**Black e18 and e1 are adjacent through the wrap. The two panels show one continuous 9 × 18 board.

Black stones at I:d5 and II:e4 form one chain across a genus-two staircase join, with liberties in both charts. — **Genus two**Black I:d5 and II:e4 connect through a staircase edge. A chain’s liberties can lie in either chart.