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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The AI uses Stockfish 17.1 (Lite Single-threaded version).
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 |
Ad-free benefits are granted automatically when you contribute text-bearing content on topic pages. The grants stack additively — posting multiple times extends your ad-free period.
Ways to earn ad-free benefits
| Action | Duration |
|---|---|
| Post a text topic | 7 days |
Posts containing only ratings without text content do not qualify for the grant.