Chess on an Infinite Plane

Actually you could define infinitely many pieces. Say, there are 6 knights on (a,b), (a+1,b), (a+2,b), (a,b+1), (a+1,b+1), (a+2,b+1) whenever either a or b is divisible by 100. You only need really lots of moves to bring them in play.

can I play?

Yes, that would be awesome. You two can play, and I'll be happy to update a diagram once a day. I'd like to watch a game, and it's fun when other people watch too and leave comments (obviously observers are not supposed to give advice).

If I can find an opponent, I'll play a game too (starting later). The winner from your game can play winner from my game, and we will learn who is the word champion!

Btw, my record in this game is not so good (1 win 2 losses - see below). I'm not an expert, but I would like to get better.

cobra vs vickalan (cobra wins)
mayapira vs vickalan (mayapira wins)
bowlinggreen vs vickalan (vickalan wins)
(other variations have been played and I'm not including those).

I'll start a thread for your game soon.

and now what?

I just started a thread for your game (here). You asked to play first, and ulfhednar1234 is the "invited guest" so I gave ulfhednar1234 White. This game will be fun to watch!

(I'll try to update a diagram once a day. I'll be on vacation July 27 - 30 so there might be a small break during this time).

I think it's possible for these games to last very long sometimes (longer than normal chess) if the opponents are about equal, but games can be very tactical and spectacular. Btw, no chess engine plays this game, so computer analysis is not possible. I will plan to play the winner of this game, or if I can find an opponent we can have a small "4-way" tournament to decide "world champion" in infinite chess!

Can I play a game too?

Yes, that will be great to have another game started. SuperSam1 also agreed to play, so your game is (here). You play White.

I'm filling the slots for a 4-game (8 player) tournament - (see here).

Good luck!

What about an expanding plane? Initially, the board would be finite, but we could invent one piece that would be able to step outside the current board, after which the board would be enlarged accordingly.

the piece could just move one square side to side and up and down

Interesting ideas. I wonder if another piece can also have the power to shrink the board (remove one rank or file from an edge). That might be an interesting way to enclose or trap pieces, or create new types of checkmates.  The end of some games might have very unusual boards (like 3x20), or large (40x40), or small (3x2).

Thanks @hitthepin. I've seen a few comments about early-game flank attacks (attacks from behind) and can they work? Usually I believe it's not a good immediate opening strategy. The king can be defended in much fewer moves than it takes to create an attack. It takes at least three moves to get behind the enemy, but the king can be defended (from each direction) in one or two moves.

But I obviously haven't considered every possible combination. Maybe I'm wrong. Any thoughts or ideas on king protection, flank attacks, etc.?

I'll add some thoughts regarding rules and tactics after my current game has finished. I'll especially consider how castling can work. Perhaps rather than "castling", we can have "guarding", with the rules the same as classical chess except it's the king and guard who move. That's the first idea that comes to mind, I'll think more as my game progresses.

They're definitely stonger than in classic chess. Consider that despite the fact that the bishop can still only occupy half the squares that the rook can, the bishop still has an infinite selection.

Proof right there that half of infinity is infinity.