A few levels for Underdark Overbright are decidedly 'concept' levels. The concept behind A Drowning was to put the player up against a seemingly impossible boundary, and expect them to push themselves through a crucible to get past it anyway. I tried to do this by making the player swim the length of an underwater tunnel far longer than was possible on one breath, in a struggle against the clock. Then make them do it twice more. This level was the problem child of the pack, and I debated cutting it until the very end.

The principle of The Swim was simple: the first time, it's an underwater time trial, where the player's own health is the timer. Dawdle, or get bitten by an underwater enemy, you lose time; find a health pickup, extend your time; the quicker you are, the more health you keep. The second swim is biosuit-assisted, so the time pressure is off, but the enemy count is higher. The third time, the player has raised some platforms in a space above that reveals air pockets below, so the space is effectively conquered.

Something the Doom mapping community is pretty good at exploring is escalation: putting the player in what seems like the worst possible situation, then letting them know how wrong they were by giving them real problems. This kind of "oh come ON" moment is one you just have to laugh at (or so I thought).

I designed the level divided into two halves joined only by the underwater tunnel, each side with a locked door, and each side with the other side's key. Faced at first with only a locked door and a pool of water, players have to dive in and swim through this tunnel, expecting air, coming to a button in front of a huge flood control door. They press the button just as they start to choke ... and the door begins grinding open painfully slowly.

Even once the doors are far enough apart to fit through, they turn out to have teeth that also have to separate, letting the player see what's beyond but still only teasing them with it. What they see is not air but a Megahealth - it'll save them from death just the same, but it wasn't the salvation they were hoping for. Finally squeezing through, they grab it, extending their lives by some number of seconds, and find the tunnel only keeps going. This time there are scattered Rotfish, and way down at the end they can see another door.

Things seem to just keep getting worse, but if the player simply commits to The Swim and continues without stopping, they'll eventually resurface on the far side with more health than they started with. Players still turned out to have a lot of trouble with commitment when they've run out of air.

Some died once, had the admirable reaction of "oh, I see, I got this" and then powered right through on the second try like I'd hoped. Too many others were compelled to flail in every direction except the clear path forward, sometimes procedurally dying every twenty feet for the entire length of The Swim as if to exhaust any other possibility, refusing to believe a level might not follow the established underwater air supply "rules."

I ignored the voice on one shoulder that dismissed them all as 'playing it wrong' and began to look for reasons why the level didn't encourage what I thought it did. I made a number of small adjustments, like cutting down underwater enemies quite a bit and restricting the megahealth-only supported swim to Hard mode (granting biosuits eventually on lower settings), but these only eased things for players who'd already made the mental leap. Making the leap was no more common.

My answer was to add a second, shorter introductory Swim at level start. Players are still presented with just a pool of water, but plenty of health items to return to if they don't get the message the first time. Right below the surface, the pool turns into a large tunnel leading to a slow floodgate identical to the later ones. The tunnel is scaled to be just long enough that players will begin losing health

• after pressing the button
• while waiting for the door
• once it's opened just far enough to reveal that they can swim right to the surface on the other side if they just hold on a little longer

Players who bail on the door the instant they start drowning have a longer swim back to the open air at the start than if they waited for the doors, but if they do turn back they can heal up there and try again. By the time they return, the doors will have closed again, so the 'lesson' is repeatable. Thus a player can't really get through the door and surface in the original starting room to play the rest of the level without at least once committing to pushing forward despite choking. This provides a much gentler example that it's okay to wait for a door like this, and that salvation (of some kind) can be trusted to be on the other side, prepping the player for the real The Swim that comes next.

Whenever the player finally gulps air again on the far side, they play some Quake of the more conventional variety, and once they grab the needed key, there's no way back but back into the water. A freely respawning biosuit lets players feel temporarily like they've been rewarded for defeating The Swim and have unlocked an easier return, but I play on this expectation. Their biosuit's 30-second timer will be ending (and putting them back on held breath) just as they begin reopening the last floodgate, and I surprise them by revealing a new swarm of Rotfish on the other side. (Now they're grateful the doors are so slow.) Back on the 'near' side, the key lets players into a big round chamber with the second key out of reach in the center.

I needed to design a sequence that involved raising platforms up out of the water in the tunnel below to expose air pockets the player can use on their third swim, and tie them to getting the last key, so that they can't do one without the other. I turn each one into a moment of danger, making the player drop down into a well to push each button and ride the platform itself back up to floor level, and of course each time they're lifted into the center of a sudden monster party. Each fight is harder than the one prior, but each platform serves to expand the navigable space in the room, so the space expands along with the combat.

As a side effect, there's now air available in three key locations along The Swim, so players can now easily and triumphantly carry the gold key back to the exit. Spotlights are activated that cast a characteristic shadow into the tunnel to help draw underwater attention, and there's a vertical bend at the start of The Swim that requires players to briefly swim (and look) straight up at the grate anyway, so they can't miss that it's open for them now.

The unusual premise of this level, and my struggles with it, led to a number of game-mode-specific configurations. On Easy and Normal skill levels, there is a one-way shortcut at the silver key that leads over a wall and down to the area with the silver door - only players on Hard and Nightmare have to return by swimming. This reserves the surprise rotfish swarm on that leg for hard skill levels, but also eases navigation for those on easier skills by making both swims go in the same direction.

Cooperative play was a different story. The limited health on the first swim and inability to share the Biosuit powerup meant the tunnel swim simply broke down with more than one player trying to go at once. This led me to reconfigure the level significantly into a puzzle that specifically requires cooperation. The arena room is accessible right away, but the air-pocket platforms only stay raised for a few seconds, requiring one player to swim while another waits to activate the platforms and provide air pockets at the right moments. Once the swimming player reaches the far side successfully, they open a coop-only back passage for any players waiting in the arena, and the reunified group clears out the second half of the map and exits the level directly.

Being asked to swim while slowly losing health to drowning damage seemed to just rattle players harder than I thought it would all by itself. Despite repeatedly blunting the difficulty and adding more design assists like the intro swim, I couldn't counteract that drowning is ingrained in players as a signal that "whatever you're doing can't be right." I won't go so far as to say that there isn't a good way to make this idea work that I couldn't find, but I wouldn't try it this way again.

A better swimming showcase would have found ways to work with that player expectation, rather than thinking itself clever for working against it. A freediving pit might have been better than a tunnel, with important goals at staggered depths: one easily reachable, one an uncomfortable stretch, and a last one dangerously deep. The player can tap out and return to the surface at any time, but "I haven't been all the way down to that final door yet" would remain an insistent motivation until conquered.

Play It

Both Copper Quake and Underdark Overbright can be acquired from Copper's Download page.