Frequently Asked Questions
When two pieces of the same type (like knights or rooks) can move to the same square, you need to specify which piece to move explicitly, such as Ngf3 or Rad8. You can enable the legal moves display in settings to help with this.
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Two engines are available depending on the mode. The default is Stockfish 17.1 (Lite Single-threaded version). For more human-like play, you can switch to Maia 3 (maia3_simplified), which runs in your browser via onnxruntime-web and uses the publicly available GPL-3.0 licensed model.
You earn experience points (Exp) by completing challenges. The formula is: Exp = Correct Answers × Module Weight × Miss Bonus.
Module Weights
| Module | Weight |
|---|---|
| Coordinate Quiz | 1 |
| Square Colors | 1 |
| Legal Moves | 1.5 |
| Board Symmetry | 2.5 |
| Position Memory | 5 |
| Diagonal Quiz | 15 |
| Route Planner | 15 |
Miss Bonus
| Mistakes | Multiplier |
|---|---|
| 0 (Perfect) | ×1.5 |
| 1 | ×1.2 |
| 2 | ×1.1 |
| 3 (Burst) | ×1.0 |
Each eligible contribution awards coins, usable immediately. 1 coin redeems 1 day of ad-free browsing (redemption flow coming soon).
Ways to earn coins
| Action | Coins |
|---|---|
| Submit a topic post (square / opening) | 3 coins |
| Submit a position problem (memory / puzzle) | 3 coins |
Coins earned from creating content are capped at 30 per day. The cap resets at 00:00 UTC; likes and staff grants do not count toward it.