Sources of HyperRogue: part II

This is the second post in the series, about the lands from versions 5.x-6.x.

While HyperRogue was not yet on Steam, Maciej Chojecki has sent me a bunch of ideas for new lands. One of the ideas was about a forest -- with forest ghosts which can walk on trees, and "timbermans" who can destroy trees and drop "axe orbs" on death, which could allow you to destroy trees too. I liked the idea of a maze of trees, but I was somewhat afraid of static mazes then (you could just run into a dead end and slay any followers easily), so I thought that there should be some anti-camping mechanism -- and what anti-camping mechanism fits the theme of a maze of trees? Bushfires sounded great, especially if you could cut the trees to make the fire spread slower! I have tried several approaches, but finally it worked as I wanted (two types of trees were required so that escaping from the fire, and stopping it by removing trees, was balanced well). Also, in the meantime I have played Hoplite, which is another small tactical roguelike. I loved some of the great ideas here, such as the stabbing mechanics -- possibly HyperRogue would develop in a different way if I had played Hoplite before... In Hoplite your character has a choice of learning one of possible skills, allowing the player to develop their character in many different ways. I miss this in HyperRogue somewhat, but on the other hand, I find the extremely simple rules of HyperRogue nice too -- and new lands would be harder to balance if multiple builds were possible. Hoplite is newer than the early versions of HyperRogue, so maybe it took some inspiration? I don't know. :) Anyway, I have copied the stabbing mechanics, and created HyperRogue's Hedgehog Warriors. In the Slavic mythology, ferns blossomed only on the summer solstice, and the Fern Flowers brought wealth to whoever found them. Seemed like a great treasure for the forest land. Interestingly, after finishing the Dry Forest, I read Maciej Chojecki's e-mail again and found out that he had the same idea for the name of the treasure.

Cocytus, the hellish version of the Icy Lands where heat creates immovable terrain instead of destroying it, was partially created before LoEM. The idea for the mechanics is somewhat inspired by Stanisław Lem's Three Electroknights, a short story where a knight steals the precious gems from an extremely cold planet, until his heat melts the ground below him. The problem with heat-based lands is that it is somewhat hard to plan your next moves here, as it is hard to tell whether a cell will melt in the given turn or not. Thus, I have decided to make it an unfinished land, only accessible to cheaters (or by getting 2000 $$$ -- which was actually possible in some versions, by using exploits). As for the name, Cocytus was one of the four rivers in Hades in the Greek mythology, a frozen lake in the ninth circle of Hell in Dante's Divine Commedy, and the ice-themed part of Hell in Dungeon Crawl -- I guess Dante is the closest to HyperRogue here. After adding the Dry Forest, I have decided to finish Cocytus too -- I have added the missing graphics, and also added the Crystal Sages. I wonder how people interpret their weird gestures? I think nobody has commented about that. Anyway, read Three Electroknights for an explanation -- the gestures come from there.

Thus, 5.x included two new lands. Version 6.0 started with five new lands...

I have already mentioned the forest idea by Maciej Chojecki. While I did not want a static maze because I was afraid of camping, his ideas actually solved the problem -- the "timbermans", and also somewhat the monsters moving through walls only, would prevent you from just waiting in a dead end. Thus I have decided to create a new land based on the mechanics, just changed the theme to a cave -- and thus the Dead Cave was created, reusing Seeps for the Forest Ghosts, and with Earth Elementals instead of timbermans, still dropping orbs providing means to go through the walls. HyperRogue already contained Orbs of Digging, which worked only in the Living Cave -- I have made them work in both lands and also in some other lands, and renamed them to Orbs of Earth. Also renamed Orb of Lightning to Orb of Storms. (Speaking of orbs, the name Orb of the Flash from the Icy Lands is based on a spell from Diablo.)

Some players on Steam wondered how a war game would work in the hyperbolic plane, and that's how the Hive was born -- and they wanted ants, so the Hyperbugs who fight there are ant-like creatures. Royal Jelly is the food of baby bee queens, and it appears as a quite valuable item in many roguelikes (ADOM, NetHack, older versions of DCSS, Spelunky HD). Again, I have tried several attempts -- in some of them Hyperbugs were invincible, in some you only received Royal Jelly by killing the Hyperbug queens, and in some there were actually three sublands, for the different Hyperbug races -- before finally settling for circles of radius 9. Note that this was before horocycles were added to the game, and even circles of radius 9 were somewhat a challenge for me at the moment... they were (and they still are) generated completely when they were created -- I think that the reason for the sparsity of Hive is that I did not want walking through Hive to use too much memory (even though it probably actually uses more memory as it is, since you have to walk longer before finding a nest).

I don't remember how I got an idea of a more complicated repeating pattern... possibly it came from a discussion with Fulgur14. I think I wanted a dense regular pattern of ultraparalell lines, to make a better use of the hyperbolic geometry. I have called it the Vineyard, since that's what dense paralell lines remind me of. (Also see some regular graveyards from the real life.) Vine Beasts appear in some addons for Battle for Wesnoth.

Satisfied with the Hedgehog Warriors, I have created some more monsters requiring special means of killing -- ones which were killed when you approached them (again a bit like in Hoplite), and ones which were killed when you moved away from them (somewhat inspired by the game Ultima, which is a chess-like game where pieces differ mostly by the way they attack, rather than their movement capabilities -- I have never actually played it, but I find the idea interesting). Also, it turned out that I could create several interesting repetitive patterns by changing the vineyard one a bit. I wanted a sea land for a long time, so I wanted to combine all these ideas into one -- a "fjord" with a regular pattern and filled with Hedgehog Warriors, Pikemen, and Flail Guards. However, this turned out extremely unconvincing, so I have dropped the fjord theme, and it became the Emerald Mines instead -- a maze of small twisty passages, all alike. (By the way, that quote about small twisty passages is from the classic adventure game, Colossal Cave Adventure -- not used in HyperRogue, but Hydra Slayer quotes another line from CCA.)

I was somewhat unhappy with the relatively low usefulness of the early Orbs, so I have created the Land of Power, where the Orbs were essential. Initially it was supposed to have fires arranged in a way similar to the ice walls in the Icy Lands, but finally, I have decided to use another rearrangement of the Vineyard pattern. The enemies were called Witches so that we have more female enemies, to complement the choice of playing a female character, which was also introduced somewhere around that time. By the way, a bit of history about this choice: players have been asking to translate HyperRogue to their languages. At first, I did not want to add translations to HyperRogue -- I did not believe in translations too much, since programs are usually translated very badly to Polish, where nouns can be in several cases based on their role in their sentence, and verbs and adjectives change depending on the genus of the noun. Most translation engines cannot handle that -- instead, they cheat by using forms which are always correct, but very ugly and unnatural. But then, I thought, let's show them how to create a beautiful Polish translation -- so I have created an engine which created nice Polish sentences, and even cared about the gender of the player character correctly.

That was HyperRogue 6.0. Then, tricosahedron has asked on the Steam forums about large and infinite circles -- he believed that the placement of Great Walls in the HyperRogue world was static, and thus there would be fixed large circles made of a specific land, and wanted to know how to find a center of such a circle. Actually, great walls are placed randomly (not based on any circles), so this question does not make much sense -- but still, his question seemed to be an interesting challenge, and that's how Camelot was born in HyperRogue 6.2. Camelot, the Knights of the Round Table, and the Holy Grail obviously come from the English legends.

Camelot required HyperRogue to be able to create made of billions of cells, which could not fit in the computer's memory. Changing these routines to also enable infinite structures -- that is, horocycles -- was relatively easy. It was Fulgur14 who wanted horocycles to appear in the game -- and the first land featuring them was the Temple of Cthulhu, greatly improving the previously quite boring R'Lyeh. I wanted the player to have to go deeply into the infinite sequence of horocycles to obtain a big amount treasures. There are many famous fictional books of magic in the Cthulhu mythos, such as the Necronomicon -- to force the player to go deep into the horocycle, I have decided that these books would be the treasure, with more valuable ones deeper in the temple, but no point to collect two copies of the same Grimoire. With the ultraparalell lines of the Vineyard, medium circles of the Hive, large circles of Camelot, and infinitely nested horocycles of Cthulhu, the hyperbolic theme of HyperRogue became much stronger -- thanks to Fulgur14 for discussing the hyperbolic geometry :)

To be continued, with the lands from versions 7.x...

Hydra Slayer released on Steam!

Hydra Slayer has been just released on Steam!

If you don't know what Hydra Slayer is: is a roguelike with a unique combat system based on the properties of numbers (inspired by some old mathematical puzzles). At first this is simple addition and subtraction, but then divisibility and more complicated properties of numbers come into play. As a general design rule, it is rarely clear which weapon is better: the more potential the weapon has, the harder it is to use (for example, a blade that can cut 12 heads at once is useless against hydras which have less than 12 heads). You will need to combine your weapons into sets which can kill hydras as effectively as possible: hydra attacks cost you health, and it does not regenerate. You can play it as a short 12-level coffebreak roguelike, or continue to the full game, filled with many different special types of multi-headed beings, lots of special artifact weapons, levels with strange topologies, and so on. Hydra Slayer's system is very clear (no more wondering whether +3 Evasion or +1 Dexterity is better, because you don't know the formulae used by the game), but hard to master. Many of the items in Hydra Slayer are also unique -- they would not make sense outside of this combat system, like the Powder of Growth, which makes a hydra grow extra heads -- which is very useful, since a hydra with less heads is not necessarily easier to kill. See the detailed list of features.

The new version (17.0 -- of course, 16.3 is still available for free) has the following features:

• Typical Steam features, such as online achievements and leaderboards, Steam trading cards, cloud-based saves, automatic updates, and community.
• Updated interface. Some new animations (watch those heads fly!) and graphics.
• Slightly updated performance.
• A random challenge, which is 10 levels long, and much more random than a usual run of Hydra Slayer. Also, a daily challenge, where everyone plays the same random challenge, and can compare their scores.
• New music, by Brett Cornwall (work in progress).
• Some minor new gameplay features: traps to lead hydras on, Orbs which provide a powder/potion effect many times at the cost of a weapon slot, and new map generators.
• Source code (except the Steam features) is included.

You can buy Hydra Slayer on Steam or itch.io. Have fun playing!

Sources of HyperRogue: part I

This is the first post in the series which attempts to list all the cultural references and sources of ideas in HyperRogue. I always want to read such things, so I write one myself too :) (especially for historical fiction, which I often find somewhat annoying because I don't know what is history and what is fiction)

Starting from the basics: HyperRogue is a roguelike set in a hyperbolic world. I wanted to create a hyperbolic game since I have learned about it, like 20 years ago. First it was supposed to be some kind of a shooter, then I got involved with roguelikes, but I was unable to find a grid which could work well (each grid works only with one specific size of tiles, and all of them appeared too large for a roguelike). Then, I have found the "hyperbolic football" pattern, and that just was what I needed!

HyperRogue started as a weird mathematical experiment, I have implemented the hyperbolic grid, some wall/treasure/monster generation, and the simplest combat system. I had some rough ideas for a quest (coming to think of it, maybe a good idea for a new land...), but this simple thing already turned out to be surprisingly good when moved to hyperbolic geometry! But one thing I did not like about the combat system: the player could just camp in a place with just one passable adjacent cell, and destroy all the enemies easily. So, inspired by the theme of Frozen Depths somewhat, I have introduced the heat mechanics, and yet another enemy which tracked its prey by heat. That was the first version of Hyperbolic Rogue, and also that's why the game always starts in the Icy Lands.

For the 7DRL challenge (version 2.0), I have decided to extend the game, and create more lands...

A desert with huge worms is referred to in JRR Tolkien's Hobbit, but Thumpers, Spice and Sandworms are a reference to Frank Herbert's Dune. Mechanically, Sandworms come from the popular "snake" games (most famous one is the Nokia, but the concept is older), and more directly, from DROD. Also, they work as an anti-camping mechanism -- every land attempts to have one. In the earlier versions, sandworms were not allowed to leave the Desert.

I also wanted some cavernous region, and I got the idea that a cellular automaton might generate nice caves. Trolls and Goblins are typical fantasy monsters living in the caves, and Seeps come from DROD again. Translators always seem to ask what a Seep is...

The roguelike Ragnarok (aka Valhalla) has a monster called the ivy creeper. All other monsters in Ragnarok took just one cell, but the ivy creeper could grow. Sadly, it was extremely rare, and thus not very prominent. Shame for such an interesting idea -- but the Jungle in HyperRogue brings Ivies back their deserved glory. In the early versions, Ivies were rarer (you would usually see just one), and thus it did not look much like a Jungle. This was changed in the later versions (4.x?), also making the Jungle the hardest early land -- although some of the hardness was apparently caused by creating Eagles more frequently than intended due to a bug on MS Windows. Later (8.x?), this was somewhat toned down again, by not generating double Ivies (two adjacent roots -- much harder than the normal ones) if the player has not yet collected many Rubies.

Ragnarok also had a level called the Crossroads, which allowed travelling between the different places quickly. Hyperbolic geometry makes this work better :)

Slimes are typical RPG monsters, and the elixir of life is the typical objective of alchemy. So, nothing really special about the Alchemist Lab, but note that HyperRogue was still an ASCII only game at that point (there were only graphical effects for Orbs, and Sandworm/Ivy segments were connected with lines). If I recall correctly, the reason why we have a rule that cells containing Elixirs of Life (or other items) are considered to belong to both colors is because it was impossible to show the color of slime beneath the item in the typical roguelike ASCII display. HyperRogue still has an ASCII option, but I no longer care much about tailoring the rules so that the ASCII display is 100% playable.

DROD also has Mimics, which try to repeat your moves, leading to quite interesting puzzles. I wanted to see how this mechanics works in the hyperbolic grid, and that's how the Mirror Land was born.

This was the last land in the 7DRL version of HyperRogue. Later came Version 3.0, which introduced graphics, and some new lands. The graphics are inspired by M.C. Escher, most notably the Circle Limit series, which are based on hyperbolic geometry.

Graveyard was the first land with a regular pattern, and Ghosts move through walls, as everyone knows. Zombies come from the Haitian folklore, and are everywhere in the fantasy works nowadays. It always felt strange for me in e.g. ADOM that a necromancer can turn a dead body either into a ghost or a zombie -- shouldn't creating a ghost require just the soul, leaving the soulless body to create a zombie? So, in HyperRogue, Necromancers are able to create both a ghost and a zombie from a single grave. Graveyard also features an invincible Shadow who follows you everywhere, somewhat inspired by Darren Grey's 2DRL, Run from the Shadow. However, the Shadow turned out to be not very interesting, just creepy. Some time later (around 5.0), Ghosts have started to appear whenever the player stopped exploring the world -- this was originally intended as a way to force the game to actually end when the player is stuck in the Living Cave, but it also brings some new interesting tactical insights of its own.

People playing the early versions of HyperRogue said that the non-Euclidean geometry reminds them of works of H. P. Lovecraft. I have not yet actually read anything by Lovecraft at that time (other than playing a RPG session in the Call of Cthulhu system long ago, which somehow turned into a math joke and had nothing to do with the actual Cthulhu mythos...), so I have read the Call of Cthulhu: swallowed up by an angle of masonry which shouldn’t have been there; an angle which was acute, but behaved as if it were obtuse. (Well, in HyperRogue and hyperbolic geometry in general, an acute angle is always acute, no matter how you look at it.... I guess Lovecraft's geometry was even stranger, or maybe he did not know how hyperbolic geometry works). Anyway, I have added R'Lyeh, with Cultists, tentacles and statues, typical things from the Cthulhu mythos (I am not an expert in these mythos --- the Call of Cthulhu remains the only book by Lovecraft I have read --- but it is hard to not know about the tentacles and cultists of Cthulhu, or the Necronomicon). IMHO R'Lyeh was the most boring land for a long time, but this changed when the Temples of Cthulhu were introduced.

Many RPGs use a rather weird system: on one hand, getting experience or powerful items makes you stronger, but on the other hand, it also brings stronger enemies. In the end, getting stronger does not actually make you more able to fight the enemies you meet, and in some cases, it is actually much better to avoid getting powerful (for example, in IVAN items which increase your hitpoints are believed to be actually counterproductive, since they attract powerful enemies, and the rest of your equipment is not sufficient for handling them). Hell's demon fighting mechanics parody that. Orb of Yendor obviously comes from the Amulet of Yendor, which is what you have to collect in many roguelikes (such as Rogue itself, NetHack, and Brogue). And the Demon Daisy was a nasty herb in ADOM, I liked the name, so it became the treasure in Hell. The pavement in Hell is somewhat inspired with M. C. Escher's Circle Limit IV (although, according to the Polish proverb, the Hell is paved with good intentions).

Disappearing floors appear in many games, DROD is again the most direct reference here. The Land of Eternal Motion was the last land added to pre-Steam HyperRogue. Feathers were chosen for the treasure, since something which would not disrupt the land was required. Phoenix feather is a powerful material in IVAN, possibly the best thing to have your legs made of.

Versions 4.x did not introduce any new lands, but they introduced music by Shawn Parrotte (4.0) and an improved graphics engine (4.2 -- it turned out that OpenGL works with the Minkowski hyperboloid model very well). There were two cases when I have asked Shawn for a somewhat specific type of music -- since Escher's art is an inspiration for the graphics in HyperRogue, I wanted music based on similar ideas of paradox and repetition, inspired by Douglas Hofstadter's Gödel, Escher, Bach: the Eternal Golden Braid somewhat. One of them was a variant of the crab canon for the Mirror Land -- a canon that is the same forward and backward, very appropriate for this place. The other one was a variant of the Shepard tone, used for R'Lyeh -- a tone which seems to get lower and lower infinitely (very appropriate for the Temple of Cthulhu which came later). Both crab canons and Shepard tones can be understood as musical counterparts of Escher's art.

That's all the lands and important features that were there before HyperRogue got accepted for Steam. To be continued!

HyperRogue 8.2

After a quite long wait, a new version of HyperRogue is ready! Compared to HyperRogue 8.1, 8.2 introduces two new lands with treasures, a new variant of Crossroads, and two new modes.

The Warped Coast is a new coastal land, based on a different grid, composed out of heptagons and triangles. The enemies here, the Ratlings, only move when you move. These two rules work together quite well, making this land quite different. The Warped Coast unlocks at 30 $$$.

The Rose Garden is full of dangerous beauty. The rosebushes have deadly thorns and irresistible scent, which is so beautiful that it forces most creatures to move towards them. On the other hand, the Rose Beauties are so beautiful that you cannot force yourself to attack them. There are ways to kill them, though... The Rose Garden unlocks at 60 $$$.

The Crossroads IV is a new layout of Crossroads, which has no walls. It unlocks at 200 $$$.

Version 8.2 also introduces the heptagonal mode, where the whole game is played on a grid made of heptagons only. As we already know from the Euclidean mode, if we replace the heptagons with hexagons, we get a flat Euclidean world -- but if we go the other way, and replace the hexagons with heptagons, we get an even more curved hyperbolic world, where less steps are required to witness the effects of hyperbolic geometry. All the lands work in this mode with only minor modifications -- for the lands based on hexagon/heptagons distinction, such as the Red Rock Valley, Clearing, or Graveyard, a pattern of "pseudoheptagons" is used, which works similar to heptagons in the normal HyperRogue grid.

In the chaos mode, lands change very often, and there are no walls between them. Some lands are incompatible with this -- this includes all the Crossroads variants (since they become quite redundant), and all lands based on large shapes, such as equidistants, large circles and horocycles (except Temple of Cthulhu and Ocean beach, which have their chaotic variants with a part of their features). Chaos mode is unlocked by reaching Crossroads IV, and there is an achievement for getting 300 $$$ there.

The Hypersian rug mode allows you to play HyperRogue on a 3D surface. This is an isometric embedding: equal distances in HyperRogue's world are represented by equal distances on the surface. To fit all the visible part of HyperRogue's world in such a way, the surface must be very twisted...

The Hypersian rug surface is similar to the one which is obtained from HyperRogue's paper model creator, or by hyperbolic crocheting. To me, it also strongly resembles lettuce... The photo also includes a sandworm, and some HyperRogue T-shirts. Thanks to tehora for the sandworm, crocheting, and ideas for the Rose Garden!

Have fun!

Note: to make the new features of 8.2 (triheptagonal grid and rose scent) work, there have been big architectural changes in movement and attacking. Everything seems to work correctly, but there might be some special cases -- if something could move or attack somewhere but it no longer can, it is possibly a bug. Please report here!

More small changes in 8.2:

• new floor graphics for Euclidean/heptagonal mode
• pure heptagonal mode fixes/balances: compass earlier, weakened closing plates, balanced the Princess Quest, sealands should no longer be generated on beaches
• activating the Palace Quest in the Overview while cheating teleports you to Princess (instead of an empty land)
• fixed the mirrors in shmup mode: shards taken outside of mirror land no longer count, knives breaking mirrors/mirages are mirrored now, mirrors/mirages created by mirrors worked incorrectly
• birds now can fly over the Red Rock Valley
• friendly creatures are now better at stabbing
• in the map editor, hotkeys were replaced by searching for a given word
• you can no longer push thumper on a boat
• Hypersian Rug mode: Home/End keys
• Crossroads in PTM didn't mirrors
• slight color changes, to help the colorblind people

Changelogs for patches are first reported on the Steam forums.