Very few people know this about me, but in addition to being a real-life cowboy, I’m also a licensed search and rescue operator in self-contained underwater breathing apparatus — that’s SCUBA to you “landies,” as we undersea folk call you behind your backs. It’s a tough skill to learn, and sadly I don’t find much use for it in the mountains of Utah.

One of the things you learn in search and rescue is how to recover a submerged object. Usually garbage or a corpse, but hopefully one day a barrel of treasure. You bring down an inflatable container that looks a bit like a hot air balloon, attach it to whatever you’d like to surface, and then fill it with air. Air brought from your own precious, limited supply. Meanwhile, the unfortunates connected to the same oxygen tank watch your gauge’s needle spin, wondering whether they’ll have enough air to reach the surface…

Intrepid adventurers about to make their first dive.

Right there, that’s what Deep Sea Adventure, one of the tiniest games I’ve ever seen, is all about: keeping your eye on a limited supply of oxygen and muttering under your breath about the hoovers who are sucking it up.

The idea is that you and your friends are a squaggle of poor divers, rivals whose poor life decisions have left them unable to afford more than a single submersible with one shared tank of oxygen. At first this isn’t a problem. Everyone takes a turn rolling a pair of dice (with only 1s, 2s, and 3s on them) and delves ever deeper into a submerged ruin. Hunky-dory. But then something happens. Someone rolls, taps deeper into the ruin, and instead of continuing to dive, they announce that they’re picking up a treasure.

Now it’s on, because the instant someone starts hauling treasure, the oxygen dial begins counting down. Haul two treasures and your oxygen depletes faster. Three, even faster. Four, you’re probably dead.

Basically, it’s a game of chicken-of-the-sea. Players don’t expend air so long as they don’t pick anything up; but wait too long and you run the risk of having your fellow divers reach the deepest trenches, the inky blackness where the highest-value treasures have gathered like untouched sea-silt. Better to grab a treasure and flipper like mad back to the sub, and hope nobody else can rival whatever you haul back.

Scrambling back to the sub…

It might sound almost too simple, but there’s still a bit more to it. For one thing, hauling treasure not only means you’re sucking oxygen, but also that you don’t move quite so gracefully through the water. Carry too many trinkets, and while you huff and puff at your breathing regulator, you might waste a turn kicking in place. More than one diver has had to jettison their load because they got greedy on their way back to the sub.

Secondly, a full game of Deep Sea Adventure is played over three rounds, each of which sees the path into the depths transforming based on the actions of your divers. Looted spaces are removed, making the route to the bottom that much shorter. Meanwhile, treasures abandoned by failed dives are compressed into mega-treasures at the ruin’s deepest point. While it’s almost impossible to get to the bottom on the first dive, by the third it’s entirely feasible. Depending on your fellow adventurers, naturally.

Because of course, the fun of Deep Sea Adventure rests in its constant (but mild) tension, the question of will-he-take-the-treasure-and-doom-us-all? arising with every passing turn. It’s a pint-sized game of psychology. Smaller than pint-sized, actually, at least in terms of how physically big the game is. Seriously, you won’t believe how tiny it is until you hold it in your hands and wonder how many copies you could fit into a single burrito.

Deep Sea Adventure: way smaller than a sea cucumber.

If I had one reservation, it’s that the game works best with four to six players. Since divers skip over occupied spaces when they move, more players means more exploration, while just two or three players might never reach the really valuable stuff. It isn’t particularly deep (haha) to begin with, so without enough people scheming over the perfect time to cut and run, a glittering pile of treasure in tow, it doesn’t really come into its own.

But as a filler game for a slightly bigger group, everyone watching the air gauge and cursing when a roll of the dice sends them deeper than they wanted or not quite enough to reach the sub, it’s just about perfect.