It's easy to forget that TSR sold more than just RPGs and wargames, even in its early days. Looking back on it now, I can't shake the sense that someone at the company might have intuited that, eventually, the roleplaying fad might run out of steam, which would prove disastrous if other steady sources of income were not cultivated. Consequently, TSR published a number of board and "family" games, one of the more interesting of which is 4th Dimension.
As it turns out, 4th Dimension predates TSR, having originally been self-published in the UK by its designer, John A. Ball. The edition whose cover is pictured here is the one TSR published under license in 1979 and with which I was familiar. I remember having seen pictures of the game in old TSR catalogs before I ever actually owned a copy. Its odd shaped pieces (which are depicted in the illustration) were of particular interest to me, as was its circular board. To my young eyes, 4th Dimension looked a bit like the holographic chess game played by Chewie and R-2 in Star Wars and that only increased my desire to own a copy.
Unfortunately, it took me some time to find 4th Dimension in any of the hobby shops I frequented back then. When I did find it several years after I'd first heard of the game, it was heavily discounted, which, while a boon for me, suggested that the game didn't prove very successful for TSR. Having owned and played the game, I can easily believe this. At first glance, 4th Dimension would appear to be a chess variant; that's what I thought it was, as I noted. However, it's not much like chess at all except insofar as the goal of the game is to capture your opponent's "king," here called a Timelord.
4th Dimension differs from chess in a number of ways, chiefly in that it uses a "rock-paper-scissors" style mechanic for capturing opposing pieces. In addition to the Timelord, each side has two Guards, three Rangers, and six Warriors. Each piece can move only space on the board and can capture any piece shorter than itself, with the exception of Warriors, which are the only pieces capable of capturing a Timelord. Capturing occurs when two pieces are next one another rather than moving into an opposing space -- another difference from chess. Because of the very abstract appearance of the pieces (as you can see on the cover), I found it easy to confuse them, even with the height differences, which made actual play harder than it ought to have been.
The game also includes a "hyperspace" mechanic that allows a piece to "warp" from its current location to a separate board, leaving behind a marker of where it had previously been. A piece can remain in hyperspace for no more than three turns, after which it must return to either its previous location or a location next to it. This adds an additional dimension to play, making strategy a bit more complex, though, with that complexity also comes confusion -- or at least it did for me. After some play, one gets used to the mechanic and it is interesting, but there's also no question that hyperspace is more of a gimmick than something that adds much depth to the game.
Ultimately, I suspect it's the gimmicky nature of 4th Dimension, coupled with the confusion it engendered in inexperienced and/or young players, that hobbled the game's chances. I still have a lot of fondness for the game, but I also won't deny that I don't have any desire to seek out my copy and play it again anytime soon. To me, it's more of a historical artifact, both of my own life and of the life of TSR Hobbies. It's a reminder of the company's early forays into diversifying its product line. Had it (and other games like it) proved more successful, TSR's future fate might well have been different. Or maybe not. I can't fault TSR for trying, though one might question their specific judgment in this case.