To be clear, I'm not talking fundamental things like the mechanics, objectives nor anything else of such nature, however I noticed that (when playing against Greedy-Two-Bot) I absolutely crushed the bot in Grand Othello while the opposite happens in normal Othello. Is it because the central edge spaces are more valuable in Grand Othello? (because in Grand Othello, having control of the middle edges (edges in files E/F or in ranks 5/6) gives you easy access to the "near-corner" edges as opposed to central edges in Othello (edges in files D/E or in ranks 4/5) instead gives you access to the "corner-adjacent" edges (edges in files B/G or ranks 2/7) which leaves you vulnerable to exploits that results in you losing the corner). I swear tactics that worked wonders in Grand Othello for me does not work AT ALL in Othello (my strategy usually revolves around near-corner edges).

Some terminologies =

Corners (CE) = self explanatory, the most valuable spaces in both Othello games.

Locations : file A/H and rank 1/8 (Othello), file A/J and rank 1/10 (Grand)

Corner-adjacent edges (CA) = edges adjacent to the corner, the least valuable of the edges because it opens up space for your opponent to exploit it to gain a corner

Locations : file B/G and rank 2/7 (Othello), file B/I and rank 2/9 (Grand)

Near-corner edges (NC) = second most valuable spaces in Othello and the next closest to the corner, because it gives you access to the corners.

Locations : file C/F and rank 3/8 (Othello), file C/H and rank 3/8 (Grand)

Middle-edges (ME) = third most valuable spaces in Othello, furthest edges from the corners. More valuable in Grand than Othello (from games I've played)

Locations : file D/E and rank 4/5 (Othello), file E/F and rank 5/6 (Grand)

Near-middle edges (NM) = less valuable than all edges except corner-adjacent edges, doesn't exist in Othello as it can only exist in boards of at least size 9 (this one is added for the sake of completeness only).

Locations : does not exist (Othello), file D/G and rank 4/7 (Grand)

Note that I used "and" here in the inclusive sense (equivalent to "OR" if you know about logic gates).

I want to spark some Othello discussion here since I want to try get better at this game (also coincidentally I bought an Othello set last week as part of my so-called "board game developer kit" :p)

This is an interesting topic @TobiasOfTheEast

I don't have much hard data, but I can share my experience of playing Othello and Grand Othello which has also resulted in unexpectedly different levels.

I'm by no means an Othello expert, I seem to be able to beat most beginners, and I've figured out some basic principles, but I regularly get beaten by anyone who has studied the game. In my head I have an algorithm of how I play, and I mostly just execute that when I play. I apply my same game logic to Grand Othello as Othello. This would make me expect to see a similar level of results between Othello and Grand Othello.

However my current ratings are quite different:
1594 Othello (186 games)
1829 Grand Othello (45 games)

But I also remember taking part in a popular Othello Medley tournament a while back and noted that I had a superb streak of wins during the Grand Othello part of the tournament (and was very average in the Othello part): playstrategy.org/tournament/Dk3DiqAW

My only theories are:
- That there are some differences between strategy required for Othello and Grand Othello, and my usual strategy for playing Othello happens to work rather well for Grand Othello
- That there are some differences between strategy required for Othello and Grand Othello, and as Grand Othello is a lot less studied than Othello, and I have studied neither, my difference in ability compared to the average player is less
- It's all coincidence

Regarding your comment about PS-Greedy-Two-Move - this bot should have the same algorithm for both games. I think I can beat the bot regularly at both Othello and Grand Othello

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