Roguelike column thumbnail ['@ Play' is a bi-weekly column by John Harris which discusses the history, present and future of the Roguelike dungeon exploring genre.]

While there are around a half-dozen major roguelikes, and dozens of minor ones, there are a good number of attributes they all share. They almost all focus on exploration of a regular grid with spaces blocked by walls and doors, and with opposing characters who also travel through the grid through mostly the same mechanism as the player. Sometimes either side may find objects with which to aid them in their goal, or they may have innate abilities that help them, but they all tend to follow the pattern laid down in that ancient game, Rogue.

Because of this, there is a basic body of information that can help players play any roguelike they may find. This week then, we present a travel guide, a document that may aid you in your journey no matter where you might end up, whether it be the Dungeons of Doom, the Mazes of Morgoth, or the Caverns of Chaos, any alliterative complex of rooms, items and monsters you might find--in short, any place worth being.

Remember: always find out the dollar-to-zorkmid exchange rate before embarking.

Click to get a better look at screenshots.

About Diagonals

There are some interesting consequences of moving around a grid-based game world. Most roguelikes allow players to move diagonally at the same cost as orthogonally, and some even allow for free movement through diagonal gaps in walls. But monsters can do the same thing, and are usually a lot more comfortable with the idea than a human player might be.

An example of this is in order. Many games have crinkled passages, with sharp edges that don't actually need to be traveled through. This is very common in Nethack, but applies to almost all roguelikes.

diagonalexample.pngNote that this Nethack corridor (see left) looks as if it's a zig-zag, but in fact, you can just go straight down it diagonally. While these passages are most common in that game, this is a property of all the major dungeons other than Rogue's.

Since the monsters take frequent advantage, of this, it is not uncommon to get struck when turning a corner if one doesn't cut it.

In this scene from Dungeon Crawl (see below), the player is escaping from a small horde of monsters. When he take the corner, however, instead of cutting it like he should, he goes into the corner space. As a result, the rat gets a free attack when he tries to move out of the corner. If the monster was something nasty, like an ogre, and he were low on hit points, that could be a fatal mistake.

cornerexample.png About Doors

One of the most underutilized terrain features to be found in a roguelike dungeon is the lowly door. Even for experienced players, it is difficult to get past the subconscious impression that they are an obstacle to be overcome, instead of a resource to be utilized.

First, how to get through locked doors. Games in which doors can be locked, especially Nethack and ADOM, typically provide some way to get by them without needing a key. These games do it by providing a 'k'ick command for breaking them down, usually setting off any traps in the process. It also destroys the door, which makes it impossible to use tactically.

Doors are a problem because they block player exploration and fleeing, but they're an advantage because one can can close them block the approach of an enemy. If the enemy is intelligent this won't help much, since he'll just open it again, but for monsters with no hands it is an impassible barrier. And if you can lock that door, with a key or a locking spell, it will deter 95% of humanoid opponents as well.

Nethack has some idiosyncrasies regarding doors that should be mentioned. Unlike the other games, an open door in Nethack is not tactically the same as an empty space. In another of its holdovers from Rogue, neither players nor monsters can move into or out of door spaces diagonally, but attacks can be made diagonally both too and from those spaces.

Dealing With Missile Users And Spellcasters

Here's another little problem. This character is in a bit of a pickle in that he he wants to go forward, but that will put him in a wide-open area, where the centaur can shoot at him wherever he goes.

defenseexample.png

It can be very difficult to survive a situation like this if the player doesn't have some means of distance attack himself, and even then, centaurs are strong and fast, so players are usually at a disadvantage here.

The proper solution to these kinds of situations is to get behind a corner as soon as possible. Missile firers and spellcasters cannot attack what they can't see, so by getting yourself out of line-of-sight, one forces his enemy to close the distance. Once the monster has gotten close enough to see the player again, he's either in melee range or close enough that the player can reach him in one turn, and in many cases strong distance-attack monsters are pitifully weak up close. Even if it's not weak, at the very least the player has a chance of destroying the threat now, instead of just getting hit by it over and over.

Another tactic that sometimes works is to get another monster between you and the foe. In ADOM in particular, missile users will not fire if there is another monster between it and the player, even if it's weak sauce, so it'll fall back to generic monster behavior: approaching the player, even though it'll be in great danger in that position. Once it's a space away, the player can kill the nearby monster, then quickly approach and slay the archer.

This tactic does not work in Nethack, for its monsters have no love for one another, but another trick, again the result of having Rogue as a direct ancestor, does. Just like the player, Nethack monsters can only fire missiles, zap wands, or breathe whatever in the eight compass-point directions, so a tricky player can almost always safely maneuver closer to an archer or wand-user by making canny use of diagonal movement, to ensure that each turn he is either adjacent (for smacking purposes), or a safe knight's move away from the foe.

Digression: It is interesting to note that this aspect of Nethack's universe is surely intentional, because some monsters are known to take advantage of it. Try getting a unicorn lined up for a shot in a room some time and you'll see what I mean.

Dealing With Wand Users

gnomedoom.pngWands are a subclass of missile weapons that are special because they are much stronger, including instant death in some cases, can sometimes have unusual effects, and because their charges are typically limited.

The textbook example of roguelike unfairness is when a Nethack gnome, a weak monster in plentiful numbers early in the dungeon, through some divine prank finds a wand of death. While it seems these death-dispensing tools are never generated right the hands of a gnome, it is possible that he found such a wand lying on the dungeon floor. Since a player cannot ordinarily see the inventory of monsters, and certainly can't without being in the space next to it, he'll have no prior clue that the monster, out of thousands, has suddenly become a opponent worthy of respect until the fatal zap.

In most games the only thing a player can really do is use missile tactics to lure the monster close then melee him; some games this means he'll only use hand-to-hand attacks, while in the others he'll at least cause him to spend some of his turns trying to whack you. But, once again, Rogue and Nethack have a weird complication here. Attack ray wands in those games have the special property of being reflective, bouncing off of walls, potentially to hit the creature that fired it, meaning, provided you survive, the enemy has an excellent chance of killing himself with the beam intended for you.

About Speed

There are two ways that speed is handled by roguelike games: player-centric, and world-centric.

Player-centric speed was what Rogue used, and many roguelikes go through a period early in their development where they use it because it's simpler to implement. Under this scheme, all monster actions occur relative to moves the player makes. A fast monster might get an extra turn every other move the player makes, or even two moves to the player's one, while a slow monster loses turns on occasion. This way, all monster speeds must roughly match up to multiples of the player's speed, which makes effects like Haste spells or speed potions very predictable. There was a trick in Rogue, that still works in some games which use more complex speed systems, where if the player drunk a potion of speed he could kill almost any monster safely, by getting into a flee-hit-flee-hit pattern; that way, the monster's turn would always be wasted in chasing the player, while the player could both run and hit on his turns.

More recently the vogue has been world-centric schemes, where there is what amounts to an invisible world-clock according to which both the player and monsters get their turns scheduled. This way, an actor's speed is measured in ticks, after every so many of which he gets an action. Under this system there can be monsters who are only slightly faster or slower than the players, and sometimes some randomization is even thrown in to make it harder to safely abuse.

Escape, Regeneration and Loops

loopexample.pngRoguelikes present a random, hostile world in which time is rarely on the player's side. In general, turns wasted will come back to haunt the player, by attracting monsters, depleting food, or plain old opportunity cost. But there are still times when the player may want to see some time pass.

It is a convention of roguelike games that characters heal much more rapidly than they would in real life, or even in a Dungeons & Dragons realm. With the exception of ADOM (which has notoriously slow healing rates unless the player takes measures), the passage of a couple hundred turns is all a body needs to go from death's doorstep to prime condition. Even this can be sped up by using the Rest key (usually period) instead of moving around or doing something, or by putting on a ring of regeneration. Yet in most of these games, monsters heal nowhere near as quickly as players, if at all.

The safest place, often, to pass healing time is on a different dungeon level. If you can get to the stairs with at least one space between you and a monster, you can escape any foe. Even if monsters are adjacent to you when you take the stairs, certain species don't follow. Time usually does not pass for monsters when you're off the level, but some, like Dungeon Crawl, try to fake time by those monsters when you re-enter the floor.

Finally, some games, Rogue itself chief among them, reach a point eventually where the player simply cannot hope to kill the monsters. There are occaisions, in these games, when it comes time to hang up one's sword, and just sprint for the goal. The end of games of Rogue, especially PC Rogue, is most times just such a mad rush for the Amulet, and then a hasty retreat: exit, screaming all the way, stage up.

Remember: he who fights and runs away, lives to flee another day.