The standard 8×8 Reversi (Othello) is the most widely played version, but numerous variants exist — from smaller 6×6 boards ideal for beginners to the expansive 10×10 Grand Othello, and rule inversions like Anti-Othello where the goal flips entirely. Each variant creates a distinct strategic experience.
Standard 8×8 Reversi (Othello)
The standard game: an 8×8 board, 64 discs, Black moves first, fixed starting position. This is the format played at the World Othello Championship and in all major competitive events. Everything else on this page is a variation from this baseline.
All standard Reversi rules apply to the starting position — see the complete rules guide if you need a refresher before exploring variants.
Smaller Board Variants
6×6 Reversi
The most common smaller variant, played on a 6×6 grid with 36 squares and a 2×2 starting position in the centre.
Strategic differences from 8×8:
- The game is shorter (maximum 32 moves instead of 60)
- Corners become accessible earlier
- Mobility compresses faster
- Opening theory is simpler
Who it’s for: Excellent for beginners and children learning the game. Also notable as a mathematically solved game — under perfect play, the first player (Black) wins. See is Reversi solved? for more details on solved board sizes.
Competitive use: Some junior tournaments and school programmes use 6×6 as an entry point.
4×4 Reversi
A minimal 4×4 variant with only 16 squares. Games are extremely short (maximum 12 moves) and easily solved by hand. Corners are immediately adjacent to the starting position, completely changing the dynamics.
Who it’s for: Primarily a teaching tool for very young children or for illustrating basic rules. Not played competitively.
Larger Board Variants
10×10 Reversi (Grand Othello)
Played on a 10×10 board with 100 squares and a 2×2 starting position in the centre, Grand Othello is the most established larger-board variant.
Strategic differences from 8×8:
- Longer games with more complex midgame positions
- Opening theory diverges significantly — central play is even more important early
- Edge and corner access takes more moves to establish
- Endgame calculation is more demanding
- Super-stable formations can be larger and more decisive
Competitive scene: Grand Othello is played competitively in Japan, where it has a dedicated following, and internationally. The Grand Othello World Championship is held periodically.
Who it’s for: Experienced 8×8 players looking for a new challenge. The strategic concepts carry over but everything takes longer to develop.
Objective-Reversed Variants
Anti-Othello (Lollipop Reversi)
The goal is inverted: the player with the fewest discs at the end wins.
This single rule change completely overturns strategy:
- Corners become liabilities — A permanent corner disc counts toward your total, so you want your opponent to take corners
- You try to flip as few discs as possible
- Giving your opponent good moves is now beneficial — you want them to flip your discs
- Zugzwang (forced moves) becomes a tool to force your opponent to flip more of your discs
Anti-Othello is a genuinely different strategic game that rewards players who can think in reverse. Opening principles from standard Reversi are not just inapplicable — they’re actively wrong. For a refresher on those standard principles before inverting them, see opening strategy.
Who it’s for: Experienced standard Reversi players who enjoy a quirky challenge; great as a party game since beginners sometimes accidentally play well by doing the “wrong” thing.
Starting Position Variants
Random Reversi
Instead of the fixed standard starting position, the initial four discs are placed randomly (with constraints to maintain legality). This disrupts opening theory and requires more adaptable midgame play.
Strategic effect: Opening books become useless. Players must evaluate novel starting positions from scratch. Midgame and endgame skills become more decisive.
Who it’s for: Experienced players who want to move beyond memorised openings or play more creative, less predetermined games.
Classical Reversi Setup
In traditional Reversi (pre-Othello standardisation), the starting position was not fixed — each player placed their first two discs freely in the centre four squares, which could result in a diagonal OR a parallel starting arrangement.
The parallel arrangement (D4 and E5 both Black, D5 and E4 both White, or vice versa) creates entirely different opening dynamics from the standard diagonal setup. Some enthusiasts play classical Reversi with both starting options allowed.
Rule Variation: Reversi X (Corner Bonus)
Reversi X is a variant that adds a corner bonus rule: when you capture a corner, you may immediately place an additional disc anywhere on the board (subject to normal legality rules). This variant intensifies the already-high value of corners and creates new tactical combinations.
Strategic effect: Corner races become even more decisive. The additional disc after a corner capture can trigger chain reactions and dramatic board swings.
Who it’s for: Players who enjoy more chaotic, high-variance games where corners create explosively large advantages.
Multi-Player Variants
3-Player Reversi
Three players each control a colour (requiring a modified three-coloured disc set or digital implementation). Players take turns in rotation; the player with the most discs of their colour at the end wins.
Strategic challenges:
- Alliance formation matters — two players often benefit from temporarily cooperating against the leader
- Corner value is modified by the three-player dynamic
- Traditional two-player strategies must be adapted significantly
Who it’s for: Groups of three who want to play together; fans of multi-player abstract strategy games.
Comparison Table
| Variant | Board | Max Moves | Solved? | Skill Transfer from 8×8 |
|---|---|---|---|---|
| Standard 8×8 | 8×8 | 60 | No | — |
| 6×6 | 6×6 | 32 | Yes (P1 wins) | High |
| 4×4 | 4×4 | 12 | Yes | Low |
| Grand Othello | 10×10 | 96 | No | High |
| Anti-Othello | 8×8 | 60 | No | Very Low (inverted) |
| Random Reversi | 8×8 | 60 | No | High (except openings) |
| 3-Player | 8×8 | ~56 | No | Medium |
Which Variant Should You Try?
- Complete beginner: Start with 6×6 to learn mechanics without complexity
- Experienced player seeking challenge: Grand Othello (10×10)
- Want something funny and different: Anti-Othello (Lollipop)
- Want to test pure skill without opening books: Random Reversi
- Playing with a group of three: 3-Player variant
The standard 8×8 game remains the richest strategic experience, but these variants offer valuable ways to stress-test your skills and approach the game from fresh angles.
Strategic Transfer Between Variants
One of the most useful aspects of studying variants is understanding which strategic principles are universal and which are specific to 8×8.
Universally transferable:
- The basic bracketing mechanic is identical in all board-size variants
- Corner control remains critically important in 6×6, 10×10, and all rectangular variants
- Mobility principles apply across board sizes — limiting your opponent’s legal moves is always valuable
- Stable disc theory (discs that cannot be flipped) applies everywhere
Not transferable to Anti-Othello:
- Every heuristic about corner value is inverted
- Mobility thinking is reversed — you want your opponent to have more moves (so they are forced to flip your discs)
- Disc count thinking is entirely reversed
Modified in larger boards (10×10):
- The opening phase is longer — corners take more moves to become accessible
- Central play is even more important in the early game
- Endgame calculation is more demanding (96 moves vs 60)
- Opening theory is less developed because the variant has a smaller competitive community
Variants for Skill Development
Each variant can serve a distinct training purpose for 8×8 players:
6×6 for Endgame Practice
Because the 6×6 game has a maximum of 32 moves and corners are closer to the centre, positions reach a pure endgame state faster. Practicing 6×6 endgames builds the same parity and exact calculation skills needed in 8×8, in a more compact and faster context.
Drill: Play 10 6×6 games against a strong AI opponent, focusing entirely on endgame counting from move 20 onward.
Anti-Othello for Mobility Awareness
Anti-Othello forces you to think deeply about mobility — but in the opposite direction. After playing Anti-Othello, players often report heightened awareness of how their moves control or give away options. The reversed objective makes mobility consequences visceral in a way standard Reversi doesn’t.
Drill: Play 5 Anti-Othello games before a standard 8×8 session. Notice whether you’re more attuned to mobility dynamics.
Random Reversi for Midgame Training
Since Random Reversi disrupts opening preparation, every game starts in a novel midgame-like position. This forces players to evaluate positions from scratch, building pure positional judgement without the crutch of memorised opening theory.
Drill: Play Random Reversi games and apply the standard evaluation checklist (corner count, stable discs, mobility, frontier discs) from move 1 as if it were a midgame position.
10×10 for Pattern Recognition
Grand Othello on a 10×10 board introduces positional patterns that don’t exist on the 8×8 board — longer edges, larger stable disc formations, and more complex corner race dynamics. Studying these patterns expands spatial awareness that carries back to 8×8.
Variants in the Competitive World
Grand Othello Competitive Scene
Grand Othello (10×10) is played competitively internationally, with the strongest presence in Japan. The Grand Othello World Championship has been held periodically, and some national Othello federations organise Grand Othello events alongside their standard championships.
Opening theory for 10×10 is less mature than for 8×8 — computer analysis tools have been applied, but the larger game tree means fewer positions have been fully explored. This makes Grand Othello partly a test of positional understanding over memorised preparation.
Anti-Othello Competitions
Anti-Othello events are held as fun formats at some Othello club events and festivals, though it has not developed a formal international competitive structure. It is primarily a recreational variant and social event format.
Digital Implementations
Most major online Reversi/Othello platforms support the standard 8×8 game. Variant availability differs:
- 6×6 Reversi: Supported by some platforms and many AI implementations; useful for quick games and teaching
- Grand Othello (10×10): Supported by some specialised platforms and dedicated Grand Othello sites
- Anti-Othello: Occasionally available as a mode in Reversi apps
- Random Reversi: Some platforms offer this as an option
Reversi Pro focuses on the standard 8×8 game, which is the format with the richest competitive ecosystem and the strongest strategy resources for players at every level.